By pulling a Beryl you mean do anything to get "Serenity" back?
I agree on that. But on the same time, I figure it wouldn't be pure brainwashing to make him an antagonist. By convincing him that it is in his best interests to go against the Senshi, it'll be harder to bring him back. Cue angst whether he can be brought back or should he be put down like a rabid dog.