Back when I watched, too!
The two-handed 'Set Shot' and the two-handed underhand foul shot. 
Even when Havlicek was a rookie in the early sixties, the two hand set shot and underhand foul shots were pretty much gone. There were a few players who started in the fifties like Larry Costello and Richie Guerin who shot them, but younger players like Havlicek grew up shooting jump shots.
My old man had a pretty good two-handed set shot.
Rick Barry still shot fouls underhanded, with great success, into the seventies, but by then virtually every other player shot fouls overhand.
Curiously enough, while the two hand set shot has disappeared, a number of NBA players shoot flat-footed, one handed set shots from distance. A lot of big guys who don't have to worry about big guys blocking their shots shoot them. But some smaller players shoot them as well.