I feel like E.L. is implying that Christian is so wild with lust for Ana that he can’t possibly control himself. I don’t agree with that.
Christian has already been established, repeatedly, as a control freak. He is obsessed with control, both over himself and other people. He prefers forethought over impulsivity. He has more than enough willpower to keep himself from mouthpunching Anastasia Steele. And yet he did anyways.
Christian was fully aware of what he was doing. He chose to overpower our helpless protagonist.
That’s not okay.
Also, did you know that intense helplessness is one of three possible emotional responses required for a traumatic event in the DSM-IV TR? Look me in the eye and tell me this isn’t worrying.