Yeah, its kind of hard to explain JKDS. It goes beyond "do I bet or not" and more "where is my value in this hand?". Lets turn it around and look at how I played it for example. I'm probably ahead here, but if I'm not I'm probably crushed drawing to 2 outs at best. Now lots of people would just jam the flop "because I'm probably ahead". Now Erpel reckoned the flop was wet, I disagree. Chances of him having any draw better than a gutshot is really small. So his range is 99, some 7X, maybe 9X, TT+ and air. Remembering I have reads and history that suggest a fairly high likelyhood of air. Its possible he has AA/KK and is spazzing out on a flop he doesnt like, that happens. Anyway, like I say, a lot of people raise/jam flop because they like their hand in my position, but all that does is fold his air. Possibly I get called by TT/JJ or 9X, but most of his calling range beats me. My 'value' comes from calling and giving him a chance to continue with his air as well as the hands I'd have gotten in against anyway. There may even be a chance he'd fold TT/JJ/9X to a shove but will bet them again. So the play of calling gives me the chance to get in against a wider (weaker) range than raising does.

Only reason to bet here would be protection, but a PSB donk 4-way is a pretty poor way to do that. Even if I have two overcards, thats only 6 outs, so around 25% chance of improving, and thats only part of my range, not to mention he acts first. The limp/caller (I didnt give stats on him) is like 60/5. He can turn up with a 7X hand here which makes leading a possible disaster, whereas with position I have the advantage of seeing him fold and knowing I only have a LAG I've seen bluff a lot in the hand.