Lawrence Taylor -- Joe Theismann Should Thank Me ... For Snapping His Leg! (VIDEO)

Lawrence Taylor says he did Joe Theismann a HUGE FAVOR by snapping the QB's leg back in 1985 ... and he's dead serious about it.

LT was speaking at the Bronko Nagurski Charlotte TD Club Luncheon in North Carolina on Tuesday when he was asked how the incident impacted his life.

Instead, LT explained how it made Joe's life WAY BETTER.

He also made fun of the Washington Redskins quarterback for the way he "screamed like a girl" at the time of the injury.

Brutal.

BTW, here's the video of the break. Enjoy ...