I think that we got pretty lucky to be included at all, and I think that the author did a very nice job representing our style of campaign, even if he wrote no real specifics.
I have finished the book (of course, I actually finished it the day after I posted) and I think that it is a TERRIFIC read for any fans of Blood Angels, Daemons, or the Horus Heresy in general. Very exciting stuff!
Now we know, Primarchs are about equivalent to very ancient Bloodthirsters (especially when the Primarch loses his focus).