It depends on why TheOtherDave doesn't like doing whatever. If it's something that he could get to like or at least tolerate by being more familiar with it, no biggie.

If it's just aggravating and he doesn't get used to it, but it doesn't come up often enough to make him miserable, then it's one of those things which is apt to happen in jobs.

If it's something that takes so many additional hours that he's running himself ragged, then reinforcing him for doing it would be bad for him in the long run.