your play is, agreed, completely stnd there is no merit whatsoever to you doing anything other than jamming the flop as every scare card for KJ completes your hand.
As for him, well it's only 100bb deep so you cant really fault his play, I imagine he would want to c/r some non KJ hands here (usually
Xs with gutshot semi-bluffs) so he really should have KJ in there as a hand to c/r as well, in the vacuum of this specific spot (with no useful pair of big spade blockers) I'd prefer to just check call and see a safe turn card before chk/raising, as once we've check raised we're going to be repping KJ almost exclusively in your opponents eyes that it's very possible to still get outplayed on pairs and spade turns, so if im going to hate my life on half the turn cards and have the nuts on the other half, i'd rather just be putting one bet in on the flop than 2 (unless I can get my entire stack in)
He never gets it in "great" on the flop (although it's a perfectly decent stack off) because his range will be KJ almost exclusively so he;s only going to find himself against hands with good equity, or that are freerolling KJ.
And I agree with Cos, fold pre, or if you must continue 3bet with the 100bb stacks but I think it's too weak personally.
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