2015 called.  It wants you to give back its clever strategy to sell XT using fear/panic about Bitcoin's impending D000M.

If you "Bitcoin is going to choke S000N" types were serious, XT would change to a different/modified PoW at the same time it attempts (via contentious hard fork) to impose blocks >1MB on the (demonstrably unwilling) rest of the system.

Why not just do an extra round of SHA256?  Existing ASICs could do that with firmware/driver tweak.

The reason you don't do that is you want to hijack Bitcoin and destroy its interesting property of being diverse/diffuse/defensible/resilient.

The sooner you fork off and stop trying to attach GavinCoin to Satoshi's coattails, the better.