The lady who hosts my Tuesday group does a lot with 2.5 squares and sews them like that. I've done it too but I don't do too much that can be done that way -- but I do a lot of things with my chain piecing to make it easy to match sets and such that way.
I rely on pinning. It is absolutely amazing to me how many times I manage to drop my pieces or sew the wrong edge if I don't...