and one that's rarely broached in these discussions.

when the 3 pt line was introduced in the 79-80 season, most
coaches and players figured it was a gimmick that wouldn't last.
it took a while to really be embraced, to the point where guys
were coaching it and practicing it extensively.

for the first decade or so, it wasn't emphasized or utilized much.
even the guys from that era who we think of as prolific 3pt
shooters weren't taking more than 2 or 3 a game.

http://bkref.com/tiny/SCfde

contrast that w/ nowadays:

http://bkref.com/tiny/Ra4lD

everyone now is coached on that shot from the age of 12, even
bigs. so when you look up a lot of the guards from that era, see
their 3pt percentages, and say zeke or drexler or jordan or magic
couldn't shoot 3s. well yeah, dude. they were only taking 1 a game
and weren't really practicing it. if they'd come along 20 yrs
later that obv wouldn't have been the case.

another example of why i'm always railing against comparing guys
across eras. what's to say a guy like russell in today's league
doesn't develop a sick elbow jumper, that he's been coached to
shoot since AAU? bigs in the 60s just weren't asked to do those things.