Do you mean Armsmaster didn't realize what sacrificing his career meant, or that he doesn't realize how much more he would sacrifice for Dragon's sake?
Because if the latter....
Armsmaster: *realization* ...I'd die for you.
Dragon: *gasp*
Taylor: You're just figuring that out?
Tony: Better late than never. Mazel tov, you two. We should hurry and finish up that bio-synthetic chassis for your girlfriend so you can both get to the fun stuff.
Dragon&Armsy: STARK!
Gah! The fluffies and feels. Somebody help me....