I've played with a few TC Renegade and Hawken barrels that had obvious pits and they shot just fine. They did accumulate fouling though. You just have to do a real good cleaning job on them to make sure the fouling is out of the pits. But I do a complete flush after a range session anyway, so it's no big deal.

Now I'm talking patched round balls here. A pitted bore may behave differently with full bore conicals or sabots. But come to think of it, I had a pitted .50 Renegade barrel that shot 250 grain XTPs in Harvester sabots quite well.