: Where'd you hear this? I've never heard that before.
: The first time we hear of or meet the Warlocks in game is
: in Myth II...to my knowledge.
I agree with Seraph. Bungie seems to have not gotten the idea for warlocks until Myth II. It's entirely possible that they were put in for less of a storyline reason, than to attract more customers; this theory seems supported due to the heavy advertisement emphasis that Bungie put on "sorcerers" with fireballs when they were advertising for M2SB when it first came out. (I have a couple M2 poster-advertisements.)
Also, Warlocks are pictured as essentially minions of Myrdred alone. Why, then, would they be organizers of the Fallen, if the Deceiver didn't get along with any of the others, especially the Watcher?
(See, Seraphy, I'm not out to get you... yet. Muahahahaha...)