I recently tried a Tank Berserker in Elite HC with Potterman and realized it's super hard to get throug the early game. Intrigued, I consoled one up to lv20/30/50 and 100 and bought some gear for those levels, specializing almost exclusively in survivability.
Berserker's Banner is a great group buff (40% dodge at max lv, among other things). Additionally, the class has tons of area CC and sustain skills.
It's not viable from the beginning (especially in Elite or Hardcore there's kind of a power drought from lv 10-20/30 where all you can do is charge up with Hatchet/Banner/Ice Shield/Howl and back out.
Enemies will be slow, their missiles will be reflected from you (if you stand in front of your allies they won't get hit as much), they will be taking more damage and they won't be hitting other members of the party as much.
Scales beautifully and reaches a point at lv30-50 where you can just facetank and make the game smooth sailing for other players. You won't be doing much damage, but then that's not the idea.
Some of the Ice Tree skills are also super helpful for more CC when your Charge is full. If you spec into the Shadow Lunge you can become a shield breaker later on to boot, as well as escape almost any situation.