Using the boxes isn't cheese, they were were placed there to use as cover, do you really think Bungie just accidentally left a big Guardian sized hole near the ramp by accident? If it really was cheese, they would have patched it by now and it's not like you can just stay down there the whole time, I just use it as respite then once I'm recovered and have a good idea of enemy placements I jump out and run to hide behind some other boxes :p