[Actually, the vast majority is simply not noticing. Beyond the occasional rare sudden movements, Robert has never really picked up on Don's ninja reflexes. Any behaviour that could have been even vaguely construed as odd was either simply accepted as normal for Don, or missed entirely.

And why would Robert notice? Ninjas no longer exist in his world. Nothing like them exists. Nothing like the kind of training they have exists. He would have no idea where to even start looking.

He is definitely usually consciously ignoring the fact that Don can fight... but, he does that with his other fighter friends, too, and until now had no real idea that there was any kind of lasting psychological difference.]

What is normal, in this context?

Don, I do not mind. Your differences are part of you. They are therefore part of the person I love, inextricably. ... I'm only sorry that I didn't appreciate these differences before.

But please tell me more about them, that I might give them the respect they deserve.

[He has... somewhat come to accept the fact you have killed people, Don. Learning about your reflexes isn't going to scare him off now.]