This thread has changed gears a little, but to bring it back to viability of the team compared to DK+4 Rets, Im not sold anymore. My DK+4 Rets still have pretty bad gear (3.8K AP; 300 resil) yet they are really starting to dominate targets.

The AoE from Howling Blast might be pretty nice for pressure, but the single target damage is actually not that high, especially with the increased health pools cata will bring. With Avenging Wrath, the Paladins can blow a single target (Preferably a dps) up in seconds, from 30 yards away, and the mana free healing is very effective, even with my awful gear.

In BGs, the 4 DK team might have high overall pressure, but getting an actual kill in might not be as easy with the fact that your burst is not as high as the 4 Rets. In arena, I see the 4 Rets as being even more superfluous since you will 5 toons DPSing, instead of 4, and in arena, when you blow up a target or two in mere seconds, the enemy team will usually give up. The 4 DK team would be able to put up its mortal strike effect, but could still end up escaping before you have time to apply more pressure, and it could also be dealing damage to you in that time frame.

4 DKs vs 4 Rets is really just the question of pressure vs Burst, and as discussed many a time, Burst is better for boxers ,as fast kills mean less time for the enemy to figure out what the hell is going on.