Repitching Yeast ...

I've never repitched before. I understand the mechanics and theory behind it -- my question is about stepping up the repitch.

I first pitched it into a 1.070 batch of John Maier's Blackened Brutal Bitter -- essentially a higher gravity ESB w/ a touch of carafa to make it appear the color of a dark brown/porter.

My dillema is whether I can step this up properly to an IPA. Thoughts?

It's not ideal to re-use yeast from one high-gravity beer to use in another. Better would be to go from a low-gravity to high-gravity. That said, if the yeast was healthy, it will probably work. Not sure what you mean by "step up". Usually, that's something you do with starters - feed them more wort in steps to build up the yeast mass. You don't need to do that if you're re-using yeast from a full batch.