[Benman]

I agree. The expectation of a bet is a combination of your pot equity (the showdown value of your bet) and your fold equity (the value you get from the chance that your opponents will fold). A semi-bluff has negative pot equity but enough fold equity to push you over the hump into positive expectation. The old definition of a semi-bluff (bet with a hand that "doesn't figure to be best") is actually in error in the modern, SSHE, way of thinking. For example, consider a flop bet into several players with an open-ended straight flush draw, but no overcards. Technically that's a semi-bluff under the old definition because, if called, you're surely behind to at least an overcard or pair or something. But you have tremendous positive expectation on your bet alone, regardless of fold equity. Therefore, I submit that it's wrong to call that bet a semi-bluff anymore. A semi-bluff would need to be a bet which, if called, has a negative pot equity, which is not true of an open-ended straight flush draw (or other strong draws). A correct example of a semi-bluff would be raising with bottom pair, an overcard kicker, and maybe a weak backdoor draw. You are hoping for a fold, because if called, not only are you behind (the old definition) but your bet itself had negative showdown odds (ie negative pot equity). But, the bet nevertheless has positive "expectation", because the combination of pot equity and fold equity makes the bet profitable.