how far a team can go is more depedenting on who is behind the keyboard rather than the class combo (between dks and warriors).

Chance is always there. Back in the days when everyone was playing shamans/paladins, my friend actually played 5 druids and star fall + typhoon his way to 2k ratings.

I think both teams could be 2k + if you only play 4, and have a good healer with you. DKs can protect the healer more is a good point though.