Went back over the old Volunteers posts on "Hairy Legs" to make sure no one brought it up before.
Very briefly, since I think most folks here are familiar with Rubicon: you spend most of the Chimera Plank rescuing the ship's AI, Haller, only for Tycho to inform you that oh no, Durandal was lying through his face and the two of you did a very bad thing.
There's just one SLIGHT problem with what exactly Tycho says to you...
So, who was -really- wearing the flaming pants, here? Admittedly, Haller's true fate is one of those "not enough information to do more than speculate" things, and he does claim that "you've been trying to do [him] wrong", but... Personally, I'd like to think that Durandal was being honest, if simply because there don't seem to be any further hints that he assimilated what remained of Haller.