What I learnt today in Poser (Cloth Room)
The calculation order of morphs on cloth items in relation to the Dynamics affects pre / post simulation behaviour. If you choose Display in Calculation Order by right clicking the parameters panel Any Morphs that show above "Dynamics" do not affect the simulation result, those below do. (I'd always wondered why some needed setting to zero on the last frame and others it made no difference.) Great you might say, all you learnt was why Poser behaves differently for different cloth items. But you would be wrong, because you can move morphs up and down the panel so you can choose whether a morph can affect the simulated cloth or not (this is how custom morphs can affect the simulation result but most pre-canned morphs don't.)
Thanks for the heads-up!
I've already found a use case for this. I am currently working on a dynamic business suit and blouse for PE, obviously in the sim I need the blouse to collide against the jacket and skirt and the jacket to collide against the skirt. No probs if in the first frame they all sit nicely under each other, but they don't as the blouse could also be untucked from the skirt. For the skirt that's not a problem, I simply sim the skirt then on frame 1 after the sim scale the skirt X and Z until it is fully outside the blouse then sim the blouse. This actually helps as the blouse has a few frames to settle before it starts to collide with the skirt, tucking it in at the waist. The jacket is more problematic. If I scale the jacket on the X axis, the arm holes move out taking the sleeves with them, which pushes them through the side of the blouse's sleeves . So in blender I added a tight cage to my jacket object added a mesh deform modifier to the jacket then edited the cage and did an Alt-S, although that still moves the arm holes out it also inflates the sleeves as well. I then export the deformed jacket as a morph target, load it into Poser as a jacket morph, sim the Jacket. Then make sure the Expand morph is below "Dynamics" on the Parameters panel when ordered by calculation order. Set the new morph so that the blouse is covered in frame 1 and at zero on frame 30 then simulate the blouse. during the sim the jacket gradually shrinks over the blouse. The same morph can be applied at a very small amount on frame 30 to reduce those pesky little poke-throughs.