Like EnglishBob said the body part  to simulate shouldn't be "conforming" anymore - the result will be better but not always. In the examples with casual_pants both shins and feet were unchanged (no chanages in pp2, everything was conformed to human figure). In the picture above you can see body part "chest" being simulated: in the top pictures "chest" is not chest any more  - pp2 was changed and it is not conformed (it is vissible on the top left picture), in the bottom one "chest" is chest (no changes to pp2, everything is conformed).

...and the result is the same :)