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xArthurDentx

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Hi everyone, I used to play a lot of HoI2/Darkest Hour and have some questions about HoI3 (using all major add-ons).

1. HoI2 had a gearing bonus for serial production, where the longer your serial run went on for, the cheaper the produced units would get. If I understand this correctly, in HoI3 this works via the amount of practical knowledge you have, which is unrelated to the length of your serial run. Considering that, is there any point to using serial production in HoI3 (except minor convenience)?

2. HoI2 used to spam you with messages when one of your units got upgraded. I kind of enjoyed that as a bit of flavor, but I can't find a setting so that I get the same message in HoI3, I basically don't get notified at all. Is there any way to enable this?

Thanks for your help.
 

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Hello Arthur,

1. In my opinion there is a gearing bonus for serial production, though not necessarily in time per unit (Not sure about that. Maybe someone knows exactly). Every time a unit from your serial order gets built, the next one will be cheaper in terms of Industrial Capacity (IC) per unit, an effect which you can easily check yourself.

2. To my knowledge, there aren't such messages once units get upgraded. Nonetheless, you can check from time to time your units (tanks, airplanes) to see if they received newer models. Sometimes the sprites change as well, but graphics is not the strongpoint of the HOI series.

Sure, it would have been nice to see the military equipment in great detail, for both majors and minors, and to differentiate the technological tree to better reflect the historical strengths and weaknesses of every combatant. Anyways, HOI3 is much better than HOI2 and HOI4, if you want a realistic representation of WWII.

Maybe HOI5 will one day surpass these shortcomings.
 

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Thanks for answering. It's true that as you build units in serial production the IC cost goes down. However this could also be because of the increase in practical knowledge points, so, let's say I build three units in serial or three in parallel. In both cases when I build a fourth unit after the three are completed, its cost will be reduced. Would there be any additional bonus from the serial production?
 

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Thanks for answering. It's true that as you build units in serial production the IC cost goes down. However this could also be because of the increase in practical knowledge points, so, let's say I build three units in serial or three in parallel. Would there be any additional bonus from the serial production?
It might be the case. In the end, the effect is a gearing bonus. Probably these practical knowledge points will also make cheaper units in the same category (besides infantry for example, you get the bonus also for marines or Mountaineers). There is a downside if you make long series orders. The order entails the hardware (tanks, airplanes) at the technological level from the moment you put the order, let's say 1938. If the series is too long, you might create in 1942 armour with 1938 technology, which will be pretty expensive (and time consuming) to modernise. This in turn will offset the gearing bonus from the practical knowledge...
 
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I can't really give any tips on land units, but build navy and air in parallel lines and importantly stagger their productions by months at a time. It's not clear what ratios are optimal, but as an example, if building capital ships, queue them maybe six months apart and when the first finishes, the practicals will throw the others many months ahead reducing their finished date. Strat bombers benefit from this too for having such high ic needs.
 

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The down side of serial builds is that they're all locked into the tech level of the first unit, and will incur additional cost to upgrade after completion. If you can forego the convenience, it's usually better to start a new unit when the previous one completes, rather than queue several of them up in advance. Having the newly finished unit appear for manual placement (default setting) produces an "available for placement" icon which serves as a visible reminder both to place the unit and to start its successor in the queue. There is no bonus aside from the "Practical" level (other than possible Minister effects), which provides the same "gearing" bonus to all units of a general type: Infantry, Artillery, Armor, Single Engine Aircraft, and so on, but decays over time. Generally, the higher the IC-days cost of the unit, the more impact it has on its associated Practical. The higher the Practical, the faster it decays. Note that some Ministers will provide bonuses to reduce Practical decay over time.

As Dr. Intolerance points out, that Practical bonus is recalculated any time that a unit completes, and applied immediately to all units of that type in production. A spectacular example of this would be Germany building a pair of BCs, one started in January of 1936 and the second 6 months later. When the first completes, the second unit will have its completion date advanced almost to the current date, resulting in nearly 6 months of IC-days saved by the increased Practical value. If you had built them and finished them in parallel, those roughly 1800 IC-days would have been wasted.

If, in addition to the two BCs, you start a couple of BBs later in the year after researching the last 1936 BB techs to 1938, you can still have them complete before the outbreak of war, thanks to the Capital Ship Practical bonus produced by the two BCs. Note that the ADDITIONAL Practical for the second BC will not give as much benefit as the first, but will still significantly affect the completion date of the BBs, and the first BB will likewise have a smaller but still significant effect on the completion of the second. By building the 4 capital ships with staggered completion dates, one of them ends up practically free.

Rather than serial builds, staggered parallel builds are by far the better choice in HOI3, although low-cost items with already high Practical values will show little (if any) benefit. That 30th new Infantry brigade might complete a day earlier if you're lucky. For Germany, building 5-10 IC and upgrading a few airfields right from the start can give you sufficient Mechanical Practical to drastically reduce the time and cost of upgrading Infrastructure in Poland in preparation for Barbarossa, to boost supply throughput, otherwise you may find yourself running out of supplies and fuel only a few months into the campaign.

There are techs in the Theory tab which reduce Theory decay, which can have a significant effect on research costs if you're doing a LOT of research in a particular field, such as aircraft, armor, ships, or various infrastructural techs. A country such as Germany, the UK, or the US can afford the Leadership costs to make those long-term investments early on, while smaller countries will in most cases never be able to raise their Theory levels high enough to make the decay reduction meaningful. The big get bigger and the small get eaten.

I'm not sure if there's a message setting for completed upgrades, but there's a LONG list of available messages which can be switched on or off (as daily log entries, pop-up notices, or game-stopping pop-ups) from the Messages button in the Menu. By default, they appear in the daily log at the bottom of your screen (which unfortunately is closed by default).
 

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Wow! Thank you @Dr. Intolerance and @Kovax for your clarifications. Really, until now I didn't get it right, how the practicals work in relation to serial and parallel building, and how Theory can help, especially the major powers with plenty of Leadership and IC to reduce practical decay in the areas where a nation invests the most. The gearing bonus from HOI2 was indeed refined in HOI3 as a good wine getting older.

Does the Practical bonus apply retroactive to the staggered parallel units? I do know, for example, that researching a tech a few months ahead of its time but with the end date in its supposed discovery year, does remove at January 1 the
ahead of time research penalty for the entire respective research technology. One might say, this is a different matter. Nevertheless does this improved practical retroactively reduce IC costs also for - let's say staying by your example - the number of months when the parallel staggered
(later) orders were carried before the first capital ship was finished?
 

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Practical bonuses for Production are indeed calculated retroactively, so if you build two units staggered by several days, when the first completes the second is likely to become available for placement the day after the first, because it received the rest of its needed IC-days due to the retroactive Practical bonus, but is not "completed" until midnight the next day. If you don't stagger the units by enough time (which may depend on a long list of factors), it will complete on the day after the first, and any IC-days above and beyond what it needed for completion will have been wasted. In one of my earlier campaigns, I built two Interceptors in parallel, and put the one at the bottom of the Production queue so it only got part of its needed IC a lot of the time. By the time the first was just about done, the second was a week behind. When the first completed, the second showed a completion date of about two weeks BEFORE the first, and those two weeks of roughly 16 IC were lost. As your Practicals increase beyond 5, the completion differences gradually get a lot smaller, and by 10 there's not a lot of difference if it goes to 11.

The research completion date will definitely change at the beginning of the year as the research from that point on is no longer penalized, and I've seen a couple of techs suddenly complete a few days early when something in the same research field completed, or I built a unit that increased Theory as well as Practical. It's much less obvious than with Production. I often start critical techs a month or two before the year they're listed for, to get a head start, and the 1.5x research cost penalty isn't that much over the course of a month or two. For a rare few situations, it can pay to research a whole year ahead, or longer.

Note that Germany, the US, and the UK have sufficient base Leadership that researching Education easily pays itself off in only one or two research cycles, and you're still way ahead of the game if you research a year ahead of time, in which case it still only takes two or three cycles to pay back the investment. Countries will lower base Leadership will benefit substantially less from a percentage increase, so the payback time is longer, in some cases longer than your country will survive if you don't invest the Leadership into something immediately useful. 5% of 20 is 1, which will pay itself off after one research cycle. 5% of 5 is only 0.25, which will require 4 cycles to pay off.

Don't research combat techs ahead of time more than a cycle before the outbreak of war, otherwise you may need to pay the penalty AGAIN to KEEP it ahead.
 
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Similarly, the "Night Fighting Equipment" tech is probably one of the most overpowered and underlooked techs. Research it ahead of time, even paying the penalty is worth it because of the advantage it gives all infantry...
 

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The down side of serial builds is that they're all locked into the tech level of the first unit, and will incur additional cost to upgrade after completion. If you can forego the convenience, it's usually better to start a new unit when the previous one completes, rather than queue several of them up in advance. Having the newly finished unit appear for manual placement (default setting) produces an "available for placement" icon which serves as a visible reminder both to place the unit and to start its successor in the queue. There is no bonus aside from the "Practical" level (other than possible Minister effects), which provides the same "gearing" bonus to all units of a general type: Infantry, Artillery, Armor, Single Engine Aircraft, and so on, but decays over time. Generally, the higher the IC-days cost of the unit, the more impact it has on its associated Practical. The higher the Practical, the faster it decays. Note that some Ministers will provide bonuses to reduce Practical decay over time.

As Dr. Intolerance points out, that Practical bonus is recalculated any time that a unit completes, and applied immediately to all units of that type in production. A spectacular example of this would be Germany building a pair of BCs, one started in January of 1936 and the second 6 months later. When the first completes, the second unit will have its completion date advanced almost to the current date, resulting in nearly 6 months of IC-days saved by the increased Practical value. If you had built them and finished them in parallel, those roughly 1800 IC-days would have been wasted.

If, in addition to the two BCs, you start a couple of BBs later in the year after researching the last 1936 BB techs to 1938, you can still have them complete before the outbreak of war, thanks to the Capital Ship Practical bonus produced by the two BCs. Note that the ADDITIONAL Practical for the second BC will not give as much benefit as the first, but will still significantly affect the completion date of the BBs, and the first BB will likewise have a smaller but still significant effect on the completion of the second. By building the 4 capital ships with staggered completion dates, one of them ends up practically free.

Rather than serial builds, staggered parallel builds are by far the better choice in HOI3, although low-cost items with already high Practical values will show little (if any) benefit. That 30th new Infantry brigade might complete a day earlier if you're lucky. For Germany, building 5-10 IC and upgrading a few airfields right from the start can give you sufficient Mechanical Practical to drastically reduce the time and cost of upgrading Infrastructure in Poland in preparation for Barbarossa, to boost supply throughput, otherwise you may find yourself running out of supplies and fuel only a few months into the campaign.

There are techs in the Theory tab which reduce Theory decay, which can have a significant effect on research costs if you're doing a LOT of research in a particular field, such as aircraft, armor, ships, or various infrastructural techs. A country such as Germany, the UK, or the US can afford the Leadership costs to make those long-term investments early on, while smaller countries will in most cases never be able to raise their Theory levels high enough to make the decay reduction meaningful. The big get bigger and the small get eaten.

I'm not sure if there's a message setting for completed upgrades, but there's a LONG list of available messages which can be switched on or off (as daily log entries, pop-up notices, or game-stopping pop-ups) from the Messages button in the Menu. By default, they appear in the daily log at the bottom of your screen (which unfortunately is closed by default).
Decay sliw-downs are bugged without editing the exe, which is easily done. The theory techs might work but many have taken note of noticing no difference with appointing ministers.

https://forum.paradoxplaza.com/foru...-seemingly-not-working.1104187/#post-24392668

HxD is an easy and trusted editor brought to us by our German allies.

https://mh-nexus.de/en/programs.php
 

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Decay sliw-downs are bugged without editing the exe, which is easily done. The theory techs might work but many have taken note of noticing no difference with appointing ministers.
I haven't verified it, but there appears to be some minimum Theoretical decay rate, so regardless of your decay rate or how close to 0 your Theory level may be, you'll always see some monthly decay. It always rounds up, and deducts that from your current level. That minimum appears to be the overriding factor if your current Theoretical is low, but at higher Theoretical values, the minister traits and pure theory techs seem to do something. In essence, they're ONLY worth researching if you intend to put a LOT of research into a specific field over a long period of time, or to get a quick +1 to some particular item that can't be boosted any other way, such as Nuclear Research.
 

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Both practical and theoretical decay in minister traits are bugged.

Just in case, don't confuse this with decay modifiers from theory techs, these work as they should.
I haven't verified it, but there appears to be some minimum Theoretical decay rate, so regardless of your decay rate or how close to 0 your Theory level may be, you'll always see some monthly decay. It always rounds up, and deducts that from your current level. That minimum appears to be the overriding factor if your current Theoretical is low, but at higher Theoretical values, the minister traits and pure theory techs seem to do something. In essence, they're ONLY worth researching if you intend to put a LOT of research into a specific field over a long period of time, or to get a quick +1 to some particular item that can't be boosted any other way, such as Nuclear Research.
This fix fixes minister traits for theoretical and practical decays. The "theory" research works fine as attested by the guy doing the minister fix.