[Tony laughs, and the sound is a little sad.] That's the kind of thing I would tell my therapist about, if I had one. Tell you what, we'll grab some Pym particles and hop back a few decades so you can say that in front of my dad, and then I won't have to worry about the therapy bills.

[Ha, ha. It's a hilarious joke, except that, actually, being told he's a good person by his childhood hero is arguably the most important thing to ever happen to Tony. And, yes, he's definitely discovered that Steve is human and has way, way too many flaws and a fist he never wants to be on the receiving end of ever again (for more reasons than just one), but there's still one tiny part of Tony that remembers that moment of awe he had back on the helicarrier, seeing Captain America in the flesh for the first time (shortly before discovering what a pain in the ass he could be). Not to mention the significantly larger part of Tony that- well. That doesn't matter. He threw away any chance of that back in Siberia.]

Anyway, you should've known that I'll never turn down an opportunity to have my ego stroked. [He tries to smile at Steve, tries to summon the ghost of his former self to cover up his moment of vulnerability. He can't quite make it all the way to innuendo, though - but that cuts a little too close to home for him, so it's probably for the best.]