The above writeup fails to mention what is arguably an even more subtle and treacherous stigma against the sweater kilt. Many males, upon seeing a woman wearing her sweater or jacket in this configuration, will immediately conclude that she is trying to 'hide her fat ass' (as the opinion is most commonly expressed). This is not an entirely unfounded prejudice, as tying a sweater or jacket this way does indeed have the effect of concealing or at least disguising the true size, small or large, of the behind.
Some self-conscious women (and indeed many men too) make deliberate use of the technique for exactly this purpose. Others figure that most people will see right through the sweater trick, and that many will take it almost as a guarantee of the aforementioned 'fat ass' lurking somewhere beneath; these people refuse to ever wear their sweater this way for fear they will misrepresent themselves. It is a sad fact that such reasoning on both sides of the gender divide is allowed to dictate behavior, even when the alternatives offer the many practical advantages described by mcc.