Uh, haven't seen this mentioned, but points are set imprecisely by feel....don't points as they wear change the timing of the bike as dwell angle changes???? I used to use a feeler gauge get the gap close then adjust further to get the correct dwell angle. At least when messing with Austin Healey's and 240Z's.
Not sure if there is a dwell meter for a two cylinder. Seems electronic ignition would hold timing more consistent.