Quote from SkippyJr:
@Troid92: Those glitches are not "useless," you might wish to post them in the SB topic.
They pretty much are, actually. Getting to the missile expansion without knocking down the elevator is neat but it's useless because you still need the X-ray visor to get to the elevator, and all you need to get the missile after that is a beam weapon. And there is no need to access the second floor of Aurora Chamber.