Oh, I agree with everyone here! :D It makes cutting pieces so much more accurate.
Some longarm quilters don't like quilt tops with starch in them because the needle makes the starch flake off into a fine white powder that gets all over the needle area. It's really a simple matter of just blowing off the machine frequently. The finished quilt can look so much better if the fabric was starched before cutting .... it's really worth doing it! :D