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i have never heard of doing this and thus have never used the play
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I think you answered your own question. Since everyone "knows" that you would bet the nut flush draw on the flop...checking it once in a while is a good way of getting some bonus action that you might not have received when it comes in since people might just put you on the naked A of trump or a move.
This thread was where Diablo suggested it to me. Garland disbelieved that checking would get more action.... but then
a similar spot came up in Diablo's straight thread. And notice how many people wrote off the possibility of a flush and said to just push in there.