Before this video, I was vaguely aware that Picard tugged at his shirt a lot, but watching him do it 130 times was more than I can bear. I admit I jumped around a little.
What I found interesting was that, while Picard preferred the two-handed vertical pull, Riker, tended to do a one-side-other-side version
[Ode To The Picard Maneuver (With Data)] (Viewer #256,214)
Also freaky: Riker sitting down
It may have been a subtle homage to Star Trek TOS. Captain Kirk was famous for tugging his uniform shirt down, because their uniform shirts were somewhat prone to shrink in the wash.