That is why the cartridge mounts are slots. If the cartridge can be put into the alignment you want, then its OK which ever distance you use. The pivot to spindle distance from the arm designer is what most of us would consider to be the "optimum" distance for the arm, allowing it to be aligned in either a Baerwald or Lofgren B. Obviously, if you are way out of specs with the mounting, these alignments could be a problem, so that is why knowing the PTS distance is always a good thing.....