"You should," Strange bluntly says, as he deliberately looks at Tyki's hand. Yes, it would heal on it's own. And yes, Tyki probably has had worse injuries. But the fact remains that here and now, that hand could be a problem. And if there's something you can fix and patch up immediately, why wouldn't you do it?

Still, Zangetsu and Tyki? That's...a pair. A slightly worrying pair, just because one of them is Zangetsu.

"Best of luck dealing with Zangetsu, by the way." If the only other person in Tyki's department that wasn't changed by Wismuth was Murders McGee, that's definitely a sign of concern.