Mike, you are pretty good on the industry stuff. I seem to recall that the "rifle" loads for the .32-20 came along in the 1920's just about the time when cheap Spanish revolvers in that caliber were flooding the U.S. market. The Spanish had been making revolvers for the French is 8mm Lebel and it was an easy change to go to .32-20, but the guns wouldn't hold up to U.S. loads (S&W's and Colts apparently had no problems). So, I understand, the U.S. ammo makers got tired of being blamed when someone's nice new cast iron revolver blew up, and down loaded the standard ammo, while keeping the original pressures for "rifle" ammo marked as not for handguns.
Have you heard this or am I more off the wall than usual?