: Wow, the Iso-Didact / Chief connection is something I never considered. I
: wonder if the Didact talking over the Chiefs actions at the end of H4 is a
: symbol of that? Though that voice is obviously the Ur-Didact since he
: talks down upon humanity.

That's what I understood it to be. If you'll recall, the end of Halo 4 is more of a monologue that I don't think any character really "hears", just the audience.

However, several times in the game the Chief is able to hear the Didact talk and Cortana cannot, because the MC asks her where is his voice coming from and she can't hear it. To me this implies a gaes of the Didact or something similar. Perhaps explaining why he wasn't composed with the other humans, perhaps the didact had the composer tuned to anyone BUT him (or someone similar enough)

The Iso is the imprint of the flood corrupted Ur. The Master Chief (in my mind) seems to have and imprint of the imprint, the Iso.

Silentium is a good book. If it had come out BEFORE Halo 4, Halo 4 would have made A LOT more sense to the first time through. When I replayed the campaign after reading the book, I noticed so many more things that made sense or suddenly fit. It is a shame though that you pretty much NEED the book to understand them, and the average player won't do that.