My 5 monk team just hit 77 and I've done every instance up to level. Aside from my occasional derp moments (hey, it's been 18 months since I played...I didn't remember he stomped everyone in that phase!) they're pretty much AFK instancing. I drive with my mistweaver in case anything goes bad (and I've finished a boss fight where the boss was at >75% health with just the brewmaster and mistweaver still alive).

I'll ask the same question as JackBurton: what makes people bad brewmaster tanks? And are you talking about in the raid context or all-around?