[Bug] armor stack_effectiveness not considered

I was modding some modules for my mod and think I detected a bug with armor modules:

Shoudn’t the average armor be calculated according the variable stack_effectiveness in the textfile?

I did some testing and figured out, that it doesn’t make any difference to the average armor if i put

stack_effectiveness = 0.98


stack_effectiveness = 0.1

or any other value

On these pictures you see that stack_effectiveness is shown correctly on the UI (98% and 10%) but the average armor is always the same (here 30.00).

Maybee i’m not understanding the role of stack_effectiveness correctly. If thats the case, please tell me how it works.