Collapsing edges?

 From:  Michael Gibson
4001.3 In reply to 4001.1 
Oh also if you want to put a Blend in there as a way to make a smooth connecting surface, you may actually need to trim away some additional space to make the gap between pieces a little larger. Since Blend makes a new surface that is smooth to existing ones, if you have things that are pretty close together it can make the result pretty tightly bent and folded.

- Michael