The Major races (as pre-defined in the corresponding RC.xml file) will always use the default values written in -Unless- there is a re-saved "copy" of this race (with the normal ID tag, but using your new & altered settings as defined in any previous Game sessions) in the C:\Docs\... folder.
If you were to delete any of these extra files, the datasets would simply reset to default values until, later on, you'd make a few changes again & play straight in. I believe that the auto-saving routine kicks in as soon as we enter the Opponents selection screen.
Soooo...
My question is, does the AI use these abilities or does it choose its own each game?
AFAIK, the AIs *opponents* pick their values in two ways by priority; 1) from the RC or 2) if they are present in the opponents listing AND as a saved extra file in C:\Docs... which would override the dataset found in #1.
If its the first one, would you have to reset the abilities to make the AI pick its own?
No longer applies since it must pick a static permanent set first from the valid RC file.
I have a feeling you are confusing pre-defined Abilities with the usual remaining customization points.
Which can always alter some values at runtime, no matter what is in the RC or the auto-saved version(s).
Right?
PS; I discovered these code patterns accidentally when i wanted to enforce a PolParty choice (at runtime) to the X-Worlds' Majors and Minors since none had a proper tag line for it. And why i also gave the CustomizationPoints slot a value of Zero for all. No Ais ever played differently than i intented after that... unless (again) i'd re-edit them live into an opponents screen setting phase to *create* a new auto-save file for any.