Betaknight, I've never noticed such problems after using this method. Fact is, that I've never been using it on big scale (like changing all pants), only for individual items (like one or two hats, etc), so maybe there were lags but too small to notice them. But if you say that it really causes bugs and that you've tested it, then probably you're right. But still, leaving small, hidden mesh with just few polygons in place of original pants and then adding real model of pants as part of jacket should solve that problem.