Subject: My impression is...
Author:
Posted on: 2011-05-15 19:55:00 UTC
...that the first-person narrative is a spirit that possesses the dummy and causes it to take the place and appearance and whatnot of the character who is narrating. As such, it's not really the canon character narrating. I think a recent mission had the agent slitting the dummy!character's throat to make it turn back into a dummy.
My guess on the second question (and it *is* only a guess) is that yes, you would need two dummies. Either that or the dummy would switch and the real canon characters would pop in and out of existence. I could be wrong, though.