... Besides, nobody banned Rick Barry from shooting free throws underhand...anybody want to claim that's a traditional method of shooting a basketball?
...
My, my, my, you sure like to put easy ones out there don't you? Every kid on the basketball court at a young age quickly discovers that is the easiest way to get the ball to the hoop. Not only is it easy, it was used long before modern shooting techniques were refined. In many ways it is the most traditional method of shooting a basketball. Rick Barry was going back to the roots of basketball, not inventing something new.
Garland,
This coming year will be my 39th as a high school basketball coach. I can assure you that if shooting the ball underhand was better, I not only teach it, I would DEMAND it! You could not be more mistaken.
Rick Barry was an outlier, and you would do well to never cite him as other than that.
Shooting the ball with two hands that have to perform exactly equally for the ball to go straight is vastly inferior to shooting with one hand; that's the main (though not the only) reason that the jump shot replaced the two-hand set shot. On top of that, shooting underhand requires the player to practice two completely separate motions instead of one; that is NOT an efficient use of practice time.
As to the long and belly putter, I truly don't believe that they are "easier" or better, all other things equal. I think anchored putting helps reduce what can go wrong in the stroke due to nerves or the like. Simpson and Bradley obviously think it helps, but those putters are still best for old guys (like me!) who have the yips.
And BTW, I don't use 'em anymore, but I don't really care who else wants to. Still have to roll the ball and get it in the hole, as Shivas says.