So i talked to a tankadin mt..

[Belarkan]

..on my server today. He was crushable, however, he said he is the MT of his guild and tanks every boss in kara on a regular basis. He talked about it like his crushability didn't make much difference on raid healers. So does his raid have elite healing or is uncrushable overrated pre-gruuls?

Well you can bypass crushes with more health and good healers.
However, if being crushable means you have to get one more spot for healer, this implies your dps race will be harder.