Steve is sure he'll pay for the double-cross later, but he'll find a way to make it up to Tony. He knows his own temper, and how his moral code is constructed, and if this younger version feels used at any point, for anything he's not in favor of, he will let them know it, and it might be violent. He doesn't want to fight himself; even if he's got a leg up where skills and techniques are concerned, it wouldn't be easy. And he really doesn't want Tony fighting him; they're finally making progress.

He stands up when Tony comes in, too, but his body language is conscientiously calm and passive, hands in his pockets. "You're terrible," he tells him with a little smile. "Don't forget we're in a church, here."

And yet, the way he angles his body toward Tony, the posture he takes---well, Stark might not be able to tell, but Steve imagines his younger self will be able to read the body language: Subtle, but affectionate. Almost proprietary.

"I have a pretty good idea what you're thinking," he tells the younger Rogers. "You're going to meet the other Tony Stark soon enough, and you...will find there's some personality conflict."

That's excessively diplomatic, but whatever. "But he grows on you. He's one of the good guys. And he's not his father."