Queuing for a random dungeon alone no longer gives you the 15% buff
Aight so did a random dungeon with my paladin yesterday to get revered with the new faction that came out with 5.2 the daily grind faction can't remember the name sunreaver something... And i notic that i no longer was granted the 15 % buff for queing up with random peps, now this could either be a bug or its intented by blizzard cuase they felt that with the new gear etc the dungeons would become to easy if they dident remove it...
They recently fixed, or attempted to fix, a bug that caused people to get this buff (Luck of the Draw) in challenge modes. Possibly fallout from that change, they might've disabled it entirely until they can make sure it can't turn on in CM's.