One problem I noticed in the swap I participated in was that people got utterly mixed up with finished vs. unfinished size, even though we did our best to make it clear which was which. So some people got a variety of sizes, for instance one person who was doing a wonky log cabin. She ended up solving it by adding a frame to each block, using three different colours for the frames so that it didn't really matter that they were in varying sizes. This is one reason why I asked for crazy quilt blocks and didn't bother about size, I figured they'd be hard to mess up. Of course, I still got a few odd ones, and several people blithely ignored my request for quilter's cotton with no metallics, but hey, I won't be the one washing the quilt over time, hopefully it'll hold up well. It does also mean that I am doing fairly peculiar sashing with lots of partial seams, as my blocks range from 6" to 12" (with some truly inventive right angles along the way!), but hey, it's fun.