Wow. Just... wow. Man, I knew that the third part of the Correspondence mini-serial would be a mind bender (mostly in how all these different elements were woven together with the source materials that spawned them), but little did I know how much of one. Bravo, Gryph!
On the 12-14-2404 "missed" letter: I've done things like this in the past. "Writing to myself" I guess you could call it, even though UF-Gryph meant for Tali to read it. Sometimes, you really do need to get things down on paper (so to speak) before they drive you insane; even if the recipient never gets it.
You have to take whatever catharsis you can find and/or make for yourself.