Or every player has a separate chance to get a book? Because if so, there's really no reason to go in parties.
Does the book drop for everyone in a party?
book of dark rituals is a 5* material, not a token.
it shouldn't. like bopp I have no data, but if not everybody take the same crystals from boxes, same should apply to the book.
Technically it could happen but it's very unlikely. There's separate loot, so it's random for everyone in party. For example, only I got the book in 2-player party today.
I was playing on Elite, but I have no idea if difficulty has anything to do with that. 8-1 mission, Weight of Darkness by the way.
The reason I started playing SK over LoTRo is that there was alot less grinding and SK is more Legend of Zelda like. But now.... the grinding for the book, and even just the pages is worse than a Korean MMO.
You don't need to get the book. You can have a perfectly happy and hyper-killing SK experience without Black Kat Cowl. Do not grind just because some other people are.
I have not seen a book drop in this Kataclysm that's currently running, so I cannot perfectly answer your question. Also, the mechanics behind material drops changed slightly in the 2013-07-30 mega-update.
However, it is still the case that materials are not synched among players, right? So, until we hear otherwise, we should assume that the Book drops for just one player. (In extremely, extremely rare cases, it might be possible for multiple players in the party to get lucky, independently. Don't hold your breath for that.)