...and remembers this time to look at the burn left on his arm, the seared tissue that he let just go on getting damaged and damaged. Remembers to feel the fear that he's maimed himself for life, that healing won't work for him this time, that physical injury is real and lasting and scary and destroys your life ever after, until you have to go step into the Future and leave your friends behind not to be seen again unchanged, because your life is so much less happy now and your friends wouldn't want you to stick it out just for them...
And heal.
"Yeah, that... basically didn't work even while I had enough concentration left to try to make it work. The pain kept calling my attention back to it. Trying to say that I was the mind interpreting it instead of the 'sensory-input' didn't help, telling myself that I was strong and delighting that I could pass through it didn't help, what helped was either dissociating from it or my attention briefly going elsewhere before it got yanked back."
"But actual plus side, I remembered to experience the fear of injury, and watch healing work against that. I think I'll have easier time asking for martial-arts training from Security, now."
(Because Keltham is rather in doubt of his own ability to defeat even Meritxell, with just a Bull's Strength and Cat's Grace and no magic and dath ilani self-defense-only or group-safe-subdual skills.)