Neither version of PAC affects skill gain, so yes, a pawn who hates doing a job will still gain experience when forced to do it. However, as pawns (obviously) can't have passions for work they hate, skill gain will be at the slowest rate, and as SpaceDorf pointed out, any attempt to keep a pawn doing hated work for an extended period is going to cause a lot of problems, so the odds of a pawn ever getting very *good* at hated work are slim.