Quarto
Unknown Enemy
Because...How come? Couldn't you just make some background news, and make his "assistant" hold the briefing?
a) A number of the briefing lines would need to be re-written - even though briefings in general tend to be mainly about getting information across, Reismann is still a specific character, and it shows. More than a few of his lines simply couldn't be said by anyone else, because they are written for Reismann as a character.
b) Any such change needs to be set up. Remember how in WC4, it's a really big deal when you walk into the briefing room and find Paulsen there instead of Eisen?
c) A number of other lines in the game from other actors would also need to be re-recorded - any time anybody says "Reismann said..." you get a big disconnect - because it's assumed that the player heard what Reismann said, but this is no longer the case.
d) Replacing Reismann in cutscenes (as opposed to the briefings) would also require Eder to make a new face - and that's obviously not something we're keen on, considering that Eder's already extremely overworked in this project.
In short, it really is fairly complicated. We're going to have to bite the bullet and prepare for the possibility in any case - but we'd most definitely much rather see Reismann come back.