I was going to ask if you need two full tanks for 4H or if you can get by with a tank and an offtank. But if you can switch specs any time you're out of combat without leaving the instance, it's a nonissue as your so-called offtank can swap to a full tank spec instantly.
Gothik is easy. Just make sure that he's on the side of the room with the bigger group, then kick his ass, or have someone else taunt then taunt that person. Either way, he's a loot bag. _________________