Cleaning burnt & cook on grease off cookware

Found this: http://www.re-nest.com/re-nest/how-to-clean-burnt-frying-pans-with-vinegar-bicarb-140547 and I have this cookie sheet like thing that came with my toaster oven that is in deep need of a clean (or the trash). I did not have a way to heat it directly with this recipe because the pan has holes in it so I put it inside another pot and performed the recipe. It worked OK. But I could see how it would work magnificently with direct heat.