I usually don't do anything, and normally I don't have any problems. However I just did a double-batted king-size quilt that I tied rather than quilting, and I really regret not doing something to the edges before I put the binding on. I had puckers, I have spots where the backing didn't get caught into the binding at all...it's a disaster and it was so much work that I've been procrastinating fixing any of it. I hate doing the binding anyway, and re-doing binding seems especially annoying!
At least it's just a quilt for myself (and I've been using it anyway, it's so cozy to sleep under!) I might decide to just chop off the binding all the way around and start over, rather than trying to remove it neatly. It's just big 12" blocks of fabric (super simple) so a little off the sides won't be too noticeable. Lesson learned, though. Next time I decide to double-batt anything (especially a king-size) I am stitching those edges down before I trim anything!