CK II - Instant building completion

[Ferrumius]

One line summary of your issue
Instant building completion

Game Version
3.0

What expansions do you have installed?
All of the above

Do you have mods enabled?
No

Please explain your issue is in as much detail as possible.
Stacking carpenter's guild modifier(from business focus I believe) and oversee construction councilor job(current steward skill is 23. I didn't test if the value is relevant or not) every building construction time becomes 1 day.

edit. I just realized i also have a book also reduce build time 20%(how to build a well)

Steps to reproduce the issue.
1. pick business focus
2. get the carpenter's guild modifier
3. sent steward to oversee construction at the province with the modifier
3. construction time becomes 1 day.

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[uishax]

Is this really a bug? Seems like EU4's coring time becoming instant when cost reduction becomes 100%, intended behaviour?

 

[Ferrumius]

To be honest I'm not sure at this point. I suspected some modifiers were addictive when it shouldn't be but I didn't do the math to check.
Since there is no guarunted way to get the bonus from book it won't be easy to exploit(?) this but still it's feels too strong to me.

 

[Mannynino]

Working as intended. You are a god of construction.

 

[uishax]

To be honest I'm not sure at this point. I suspected some modifiers were addictive when it shouldn't be but I didn't do the math to check.
Since there is no guarunted way to get the bonus from book it won't be easy to exploit(?) this but still it's feels too strong to me.

It doesn't seem that powerful, its not like you get them for free. Moreover you still have to get tech to build... This is a very specialized path and should be comparable to say a duelist focused or satanist character.