Here are a few words from Tommy Tomasello in his 1991 Golf Illustrated interview:
GI: What happens to the shots of a player who executes these moves?
Tomasello: The player will immediately hit the ball higher and straighter, and substantially longer. The flight pattern will be dead straight to its apex, with the ball falling a touch left or drawing fractionally as it decends.
I wonder what the impact of today's equipment, some of which is designed to help players get the ball higher, has on this.