Ambassador said:
2) because overall it's more effective to build FAAs, stability-wise. You shouldn't build only FAAs, you should build every sort of manus, including a fair share of FAAs.
FAA's not only invest 5d/month apiece in stability, but they also reduce stabcosts by 1% (cap at 50%). So, you get automatic investments and you have to invest less to get a level-up.
I'm sorry this argument won't fly. You can't build as many manu's as you want - the price escalates quite quickly. Every FAA you build is a refinery you will not be able to build at a similar price.
At some point no manufactory is worth it. Perhaps this is when they start costing 5,000 d each, perhaps 10,000, perhaps 2,000. But no matter what at some price they aren't worth it. And the price is driven by the number of manufactories built, so each refinery you build jacks up the cost of fine arts academies and vice versa.
So in arguing that he should have lots of FAAs you're arguing that the FAA is more valuable than a refinery. And whether that's true depends on how much time you spend at +3 stability. At +3 the 5d per month from the FAA is completely wasted.
Now it is true that when you are investing all of your money in stability the 1% reduction in cost of the stability point by 1% is more valuable than a 1% increase in trade income (well technically 1% of base, so maybe more like 1.5% to 2% depending on your trade efficiency). But, broadly speaking, if the proportion of all of your revenue from trade is the same as the proportion of that revenue that is typically spent on stability (including research from the refinery and stab from the FAA), then the two are a wash.
If all of your income came from trade, then a 1% increase in trade income (which means you'd have trade efficiency of 100%) would have exactly the same value as a 1% reduction in stbaility costs when you are investing everything in stability. If 1/3 of your income comes from trade, then a 1% increase in income is just as good as a 1% drop in stbaility costs if about 1/3 of your income goes into stability.
In other words, under your approach, I think that unless the 5d per month from the FAAs adds up to about 1/3 of your monthly income (assuming 1/3 of income from trade) you'd be much better of building refineries for the extra trade revenue, and spending that revenue on stability.