Lets take a second to consider the mechanics of this idea. First lets say that dots applied somehow gave titan damage mitigation along with threat management. You already have sustain, be easy to keep titan healed with that plus physick so there is that. But as a tank job arc would have to go through some major modifications. I could go on with thoughts about how this would work I could only though compare it to earth tanking in DCUO where the pet absorbs and mitigates damage taken then the player maintains buffs through abilities.