Wary resentment doesn't reach John's expression. All it does is burn, coiling in his gut as John does his best to tread the line between succinctly answering the question and revealing too much.

"I have never attempted to name it. I've always known what it was, there was no need to call it anything other than magic."

There is no need to lie about that, at least. John has known his ability for what it is, just as he knew the way he relied on blood and bone and pain distort the way it was meant to be used. Innate ability recognizes the sense of being overextended, bent out of place.

"But I must admit, I find it difficult to describe what it feels like to use. Do you find it easy to separate the physical sensation from the abstract sense of...your abilities?"

Abilities is appropriately vague. It allows for focus on the more traditional healing Isaac does, rather than the way his body had knitted back together, bones cracking back together as blood-gouged flesh slopped over deep tears. What did that feel like, John wondered. More or less painful than the slow agony of a body repairing itself naturally?