Although I too have heard a lot about pitting & accuracy in the same breath...I've actuallyhad the opportunity to test/shoot a TC barrel with pitting and it shot as perfectly as a new one off the line.

Now I'm sure there are degrees of pitting of course...and if there are large deep pitts / excavationsin the bore walls that would allow fire & gas pressure to get around a patched ball, there might well be variations in shot to shot consistency and subsequent accuracy issues...the pitting in the barrel I tested was not deep and apparenty had no effect at all.