Oliver doesn't miss the flinch, but he's not sure why Derek does so and he shutters his expression quickly enough that Oliver knows not to ask.

"I think," he adds after a quiet moment, "if anything does ever happen to me and I can't make a decision...Felicity's word is as good as mine."

He's never really thought of this before, has always resigned himself to knowing that the sort of life he leads is heading down a certain path. Lately, though, that path hasn't been so dark, and Felicity's saved him enough times in the past that he'd trust her-- even if he wasn't completely in love with her.