This probably betrays an embarrassing naiveté on the Drunkablog's part, but after Idaho Senator Larry "shake hands, pard" Craig stared through a crack into the undercover cop's restroom stall; after Senator Larry Craig tapped his foot and the cop answered by moving his (no doubt suggestively) "up and down"; and after Senator Craig waved at the officer from the next stall ("you-hoo!"), what was supposed to happen? Would one guy join the other? That seems rather risky. Would they reach underneath the stall divider? To do what? And whatever it was, wouldn't it require extraordinarily long arms? Or would they sit or kneel on the floor? Too gross to contemplate.
Maybe the foot-tapping is code! "Meet me at the Holiday Inn Express, room 620. Bring cold cuts. And a six-pack. Not domestic."