HI, and thanks for the FAST reply.
The reason why a posed model is sculpted is because some muscles, tendons and other stuff (clothes) behave differently when in rest pose (either T or A) and when in "action" pose. We model secondary forms unposed and then do tertiary forms (skin folds, muscle bulges etc) when the pose is decided on.
Regarding your answer involving PP. I will try it, but, doesn't in only do surface bumps?
Or to ask it differently: How can I get actual surface change with a normal map?
Or are you saying I should bake Displacement with PP? - the tooltip says "Baking displacement with PP may produce bad results, because PP does not work well with displacement"