In tournament play, a short stack shoves all in and two larger stacks call. The two larger stacked players, without conversation, check out the action in attempts to have a better chance at the showdown to knock out the short stack. An example of this is discussed by Bobby Oboodi and the commentators during the WPT Borgata Open.
Link here World Poker Tour 10, E09 -- Borgata Poker Open - YouTube between 7:25-9:30.

Jin Wong, an amateur player, fails to call because he was unaware of the implied strategy of he and Bobby checking it out till the showdown.

I pose this question out of a difference of opinion between 1downswing1 and I, he says this strategy is collusion and cheating. I said he's a dumbass for posture betting me out of a hand, when we would have knocked out a short stack had he let me see the river. What do you think?