It works, kind of. If you do this, don't get too carried away with widening the slots, or the arrow will drop into the slots when you draw or bump the arrow or bow. I noticed no accuracy difference by doing this. I prefer to trim the back flat and leave no gaps for the arrow to fall into. JMPE.
With fletching like Blazers, Vanetec, etc, there is little advantage to doing this. IMHO