Oomis, I was merely trying to point out why a snowsuit might be permitted for certain situations, such as skiing. In no way do I agree that that means that wearing non form-showing trousers is therefore also permitted. And nor do I mean that a girl should decide she can take up skiing as a regular hobby or sport so she can wear a snowsuit.
It’s like the heter with showing hair at the front – a specific ruling was given by R’ Moshe for a very specific sheila and it has somehow been twisted to become a worldwide ‘accepted’ ruling.
A girl who respected herself and the image she gives across would not even ask questions about ‘who says that this is assur?’ – as FNY said, this comes from pettiness.