Reset can happen for main character (i.e. you) because you can loose stats needed for some advanced skills, but situation with companions is a bit different, as they get their advanced skills from quest.
Also, in all similar situations when you're afraid that your choices may produce unwanted results, use option to save game (and probably not quicksave, just to be on a safe side).
Even in case there would be some unwanted results, you can always restore from saved position made before crucial decision.