I was in a group for Expert Roulette the other day with a "non-AOE" DPS. It cost us all of 3 minutes. Barely the time worth a 300+ thread on the forum. Honestly, I see more time lost from random AFKs and disconnects than I do from parties with a non-AOE DPS. While it is inconvenient, the cost isn't much if the other 3 players do their job.