The beauty of having a tank spec custom tailored for your box team set up is that.YOU control the dps and can benefit most from the buffs, HOWEVER in raids you'll often find it is NOT enough, and I agree whole heartedly that if you plan to raid you better come correct, otherwise OTHER players will treat you like some scrub who doesn't know shit about dks.

This doesn't mean that you can't use a traditional tank spec and not do well boxing, I myself went that route with my druid. Just keep in mind YES it will work but won't be optimal for boxing... Up to you in the end, yet if I were you I'd try it out and see, you may find that it works much better than you give it credit for!