The thing to remember as far as the truth of anything in the compendium is concerned... it is written by Derek Karlavaegan.
Anything said in it represents things he believes or simply heard and wrote down. In that sense, anything he says can be wrong. And if the games contradict it, we can choose to see that as being to case.
Therefore, the companion *could* be both completely canon and contain misinformation. Nothing he *says* in it need be true for the book to be canon, because if it is canon, it simply means the authors have created this character in Daventry, by the name of Derek Karlavaegan, and he wrote this fictitious book... which could be full of rumors, superstitions or even lies! (though I don't think Derek is actively trying to deceive).
And if the authors were trying to do this creative device justice (the fictitious author device) there probably would be some falsities because being an imperfect author writing about something he has little ability to verify, they are bound to make their way in there!
Last edited by Kiramin; 09/13/2011 at 11:34 am.