I think this is normal behaviour - good isn't it? Poser should calculate the collisions to avoid poke-through on dynamic clothing. Sometimes it fails, and sometimes the intermediate steps look a bit scary; but it usually succeeds in the end. Situations where it might not are where the clothing is "pinched" between body parts, so that there's nowhere for it to go; and some clothing just doesn't seem to work in the cloth room, due I think to the way it's made. Looks as if his pants could do with the dynamic treatment too. :)

True about the pants but I don't want to push my luck. Well everyone said youcouldn't have poke through like that. That's amazing! I'm so happy about it. I'm trying some different poses. Oh and different pants. Love esther

I always thought if the clothing looked so awfullypulled and stretched in the intermediate steps itg meant that the animation was failing. Love esther

Yes, I think I missed the point of your original question. Normally, if there was poke-through before you started the simulation, conventional wisdom would say that it wouldn't work. Conventional wisdom is sometimes wrong. :) In this case, I think the weirdness you see during the intermediate steps is the simulator sorting itself out. If the initial poke-through is too bad, it doesn't sort itself out and you get a failure. Just guesswork on my part, I haven't experimented enough to know the answer.