I've seen this theory on a couple forums and I wholeheartedly disagree unless it is the same bet you'd make on pure bluff. If you want to semi-bluff, then great, that is one of the hardest things to defend against, but do it wisely. There is a subtle difference between semi-bluffing and betting your draw. Semi-bluffing is betting with the intent to win the pot right there. Betting your draw is betting into others without caring that they'd fold. The good thing about a bluff is that you can get away from your hand immediately if you're reraised. The key point is that betting draws gets expensive and should only be done as often as you want to bluff, not all the time. That is like saying "Always raise on the button". Easy to play against.

Reason 1: Betting your draw just gives you better odds when you're reraised. Let's say that you have a nut flush draw and bet $10 into a $10 pot figuring that if you're called, you're getting 2:1 odds. Now, let's say that you're reraised $20. So now you can call $20 for a $40 pot. This is laying you proper odds to call (without considering reverse implied odds or the fact that you may face an all-in bet (or even a pot-sized bet) on the turn when your flush misses. Now you've just put in $30 into what was a $10 pot. If you had check-called, you'd have put in $10 into a $20 pot...cheaper and better implied odds.

I've punished these types of players simply by raising the crap out of them with just top pair. These types will always call with their draws and I'll win more than my fair share. I love it when people call all-in on flush draws, don't you? So why would you become one of them? Keep the pot small until you have the best of it.

Reason 2: What if there is a raising war after your bet and you have to fold? You would've witnessed the raising war after you had checked and could've gotten away from your hand much cheaper.

Reason 3: More importantly, if you're the one betting and you don't have the best hand then you're going to get the 2nd best draws out of the pot and you don't want that. I mean that if you bet and get raised, then the other players think that there are two strong hands and will probably get out. Also, they're no longer getting pot odds to chase their draws and will fold. By having worse draws or mediocre hands leave, you're decreasing your pot odds in some cases. For example, if you act weak by checking and let someone else bet, that player may get called in several places, now giving you great odds on your flush draw instead of facing a reraise and getting the callers out. I know that flush draws don't often pay off after you hit them because they're so obvious, so a lot of people like to bet them for deception before they do hit. I think it is fairly obvious when I'm calling bets and a flush draw hits and then all of a sudden the bettor isn't scared and bets large. I won't pay that off. Typically when a scare card hits, any large bets are either pure bluffs or quality hands.

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