If Jack hadn't acquired a taste for the random eccentricities of the Time Lord, this entire situation might have proven a bit more than he could handle. However, given his previous experience with the Doctor, Jack managed to take this all in stride and only ask, "It's not gonna hurt it, right?" Because Kate wasn't there to ask and he felt morally obligated to pick up the slack her absence left. Also, it was a sentient sort of a life form that, so far, hadn't posed much of threat to anything but Headmaster Snape's sanity.

The Captain grinned at the...thingy, watching the bout between regenerations pertaining to frequency modulations or the like. Over their heads, he shot an amused quip towards the two Doctors who seemed better suited for getting on. "I don't see how you all manage to teach a single class."

Then again, Jack had a hard enough time teaching his not-confusing-science-class without destroying the entire school, so maybe his confusion was just relative. "Okay...should I do anything? Stand on one foot?" he asked, holding the thingy'd up infant, now very carefully. It wasn't that he was uncomfortable being this close to rigged up scientific devices of the Time Lord persuasion, it's just that he kind of was a little bit. Maybe.