+1 on the question of sleeping head to toe.
The 2 sets of short corner support poles are diagonally opposed to each other (i.e. LF and RR). That would imply that overhead clearance is not equal across the ends of the shelter. To wit, when viewed end-on, clearance decreases from the supported corner (LF) to the adjacent one (RF).
Maybe I'm looking at this wrong, but that's the impression I get, even though Henry's diagram shows both sleeping bags head to head.