hi daddywagsmusic - yes, that is what we are saying, but I think the point is, what needs to be perfectly symmetrical are only the parts of the mouthpiece that interact with the moving parts of the reed (i.e. the tip and the side rails of the facing curve), as well as those parts that deal with the air stream (chamber and baffle).
please correct me if I am wrong on this anyone...
and also, the other thing to remember is that I am only talking about slight imperfections in symmetry, not major imbalances like you find on some mouthpieces.
The reason for my initial question was that I noticed that a lot of refacers go to extraordinary lengths to make their pieces absolutely symmetrical in all aspects, but I was wondering why many pieces that have slight non-symmetrical aspects play just as well if not better than other pieces, that for instance, have a more perfectly symmetrical window curve or perfect side rails at the furthest point away from the tip. From my most recent experiences I am learning that what is most important is the facing curve, facing rails, and facing tip, as well as the balance between these and the baffle and chamber.
anyway, just my thoughts.
thanks guys.