Tank dps and Diminishing Returns

I see an awful lot of posts about the super aggressiveness of tanks outputting dps at all costs and in a vacuum without relating to the group as a whole.

I purpose a discussion on the sliding scale of tank dps vs survivability vs healers abilty to dps.

For example, if a tank that pulled 600 dps attempts to get an extra 50, but due to changes in survivability the healer dps goes down by 100. That would be lose of 50 dps.

Also, please add some tricks you do to get they extra dps with minimal or lessened Healer impact.