Warriros can Tank 1 juggernaut or a knight and soldier just fine.

Its when the warrior has to tank 2 juggernauts or 2 sets of knight and soldiers that there becomes a problem, a problem that's easily overcome as a paladin.

If you keep the warrior as an Off-tank, then yeah Turn 4 can be done by a warrior but its 50-100 times easier with a paladin.

Twintania is also easier with a paladin, since they can cycle through their mitigation cooldowns to eat death sentences with.

The point is though why bring a warrior who's a bigger burden on healers then the paladin?