Rog, if I were trying to make 2"-square holes, then your suggestion makes sense to me. But, I am trying to make small holes, maybe a half-inch to one-inch square or rectangular. I don't think that I can work scissors into a hole that small.
I'm inclined to centerpunch corner holes with a nail, then drill, then abrade, then polish. Plus, I think I better wear eye protection, because there is going to be stuff flying everywhere.