... but specify that we're playing Kaplan inversion such that 1♠ shows 0-4♠ and, for the sake of argument, 0-11 points, and 1N shows 5+♠s and 6+ points.
The same arguments for 2♥ still theoretically apply, but with the opportunity to show your 5th spade, do you still eschew it?
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Separately, but while I'm considering Kaplan inversion, how do those people who play it play the auction 1♥ P 2♠? With many partners I'd play this as a weak jump shift, but that seems to lose much of its value here - especially if you play Gazzilli over responder's 1N bid.