I'm curious, in what way? It seems to me Sebazy had to have exceptional gear (including VIT gear she had to buy/collect that a white mage wouldn't usually worry about), a unique stat allotment (which takes a considerable amount of grand company seals, probably twice over as I assume Sebazy won't want to remain speced for VIT permanently), a good grasp of the Titan fight, and a group of 7 other people willing to give an odd-ball, unpracticed, method a try.
I can't imagine many people are going to put forth all this energy to have a WHM tank Titan when arguable its easier and more reliable to let traditional tanks handle it...and even if they did, would it be game-breaking in any way if a few groups did?