"I could say the same for you." For pretty much all of that - he knows that Conner can take care of himself, in terms of pure resistance to damage and capability to dish it out, he's got Tim beat - but it's the other stuff he's a little lacking on. Well, okay, if it was just blending in with normal people, Conner would have him beat there too. But with unknown xenians and magic just permeating the streets, he feels justified in not wanting anything to happen to Conner, either. "If Bart was here, it'd be a lot like the old days."