Greetings,
The answer is something that you will not be able to implement.
In short. Proper Weight Painting on the designers/developers part eliminates this issue. Holes, lack of garment movement, and skinthrough, are all symptoms of one of the following.
1. The garment was not properly weight painted using Avastar, or other 3d Development application.
2. The garment was weight painted on a model other than the intended body to be used on. ie.. you weight painted on TMP but then packaged for Legacy. Since TMP has not been updated since they closed their store which was some time ago from what I read. The result is holes, and skin through the clothing.
I'm not sure why someone stated "Interesting Advertisement", since this is obviously a problem. However, they did mention something worthwhile, in stating "Always try the demos", and if you can alpha them out, then by all means go for it. If you can't then don't buy.