Its been so long since Ive run DK's both solo and as a team, but I do recall there being a difference. I.e. 2H with specific rune on a particular stance, vs dual wield with two different runes or enchants, for a different stance.

Not only that, but its no secret that unless as a boxer you have your keypresses done just exactly perfect, a GOOD solo player can out dps one of your team members. Did you happen to ask this "ragger" if he would share his rotations or was the conversation just a QQ fest?

Remember the guys name?

Got a link for him? If I were you, id start by comparing his gear to one of your characters. Perhaps theres a clue there, before you go and start rethinking your setup. Besides, arent you also healing with your healer?