Duplicate proficiency increase

[Trainedchimp]

So when doing some theory crafting my friend and I came accross the feat "Canny Acumen" which you "Choose Fortitude saves, Reflex saves, Will saves, or Perception. You become an expert in your choice." If you select one of them when taking this feat and then later your class feature also says you become Expert in that choice what happens? Do you just loose out on that class feature?

[Themetricsystem]

Yes, you'd lose out.

You do always have the option to perform Retraining using your downtime to change the selection of that Feat itself or to simply change you choice you made with it so you don't lose out.

Ya just need a bit of time off adventuring to accomplish it.

[breithauptclan]

You would not combine the two proficiency increases into a higher proficiency level. If two things give you Expert proficiency, then you have Expert proficiency.

In the scenario of Canny Acumen and a class feature both raising Reflex saves, you would be losing out on the benefit of the Canny Acumen feat. That can be fixed with retraining, and the GM may even let you do that for a reduced cost (time or money) since you are in the process of leveling up and it is a class feature that is making something else redundant.

[Gisher]

Canny Acumen also bumps your choice up to Master at 17th level. So you might have some levels where you overlap at Expert with your class features followed by levels where Canny Acumen is beneficial again.

An Investigator using Canny Acumen at level 1 on Fortitude, for example, benefits from levels 1 through 8, won't benefit from levels 9 through 16, and benefits again from levels 17 through 20.