The main problem I had when cutting it your way is if my cutter went crooked and I was cutting, for example, a three in strip of fabric, I had to pretty much put aside that piece for scrap or try to salvage part of it. But, if the three inch strip is under my ruler, it is completely protected. Then if I cut a little wonky my 3 in. strip is fine and I can square up that little wonky part and only lose about an inch or less of fabric. While both ways may be totally accurate as far as cutting. I waste less fabric with the strip I want to use under my ruler.