Dave: This is not an example of a trick play. This is a mistake in the choice of joseki by White - nothing more. I think it should be renamed or eliminated.
Bob McGuigan: This brings up the question of just what is a trick play anyhow. In a sense they all depend on one player making a mistake (and getting tricked). There are two types of trick plays I have noticed. First one side plays an unusual move and the "natural" response by the opponent leads to an unexpected bad result. The second lures the opponent into making a joseki mistake (like Danoontje's third example). I guess some moves are trick moves only for weaker players, but I am not sure where to draw the line in deciding whether a move is a trick move or just a joseki mistake.
danoontje I agree that this is not a clear example of a trick play. But trick plays and josekis have a really close connection, "one cannot be considered to understand joseki without knowing about trick plays" to quote a compendium of trick plays. In this example black sets up a rather unusual formation to invite white to enter the corner and test his joseki knowledge :-) I played this many times, and many people have chosen the wrong joseki, thats why i added it here. But if you rather want to call it "joseki mistake 1" im fine with that too.
Dave: I think the common usage of "trick play" is something that is less than the best - not just unusual. One player chooses it expecting to exploit an incorrect response from the opponent. So there ought to be an "honest" alternative that is objectively better. I do not see that here. Rather I think Black's play is ideal. White manages to make it even better of course. :-)