[Archer knows his response should be to tell Kimblee not to kill the other version of himself. He should be irritated that Kimblee would even consider that, especially given what they're going through to try to bring him to this world.

But he doesn't say that. This must have upset him more than he thought it had.]

...He didn't act on it, but I know he was working out how best to...

[He can't bring himself to finish, shaking his head instead.]

Why the hell did he think that was a good idea!? We're-- We're friends!