Going into Harry Potter mode for this weeks nightfall is definitely not cheesing. It's making the most of the environment. If it were some form of cheese all the enemies would despawn or something. For that simple fact I'm going to answer yes I was able to do this weeks nightfall without any cheesing. Another simple test to see if this is a cheese. Ask yourself has Bungie patched it yet? The answer is no!!! Bungie are pretty damn quick at patching actual cheese spots and tactics (not all but most). The fact that they have never patched or mentioned this as a cheese goes to show it is not a cheese.