I liked Coupland but hated Brian

I admit Coupland did some VERY questionable things in the film but I just dislike Brian more. In the beginning of the film, Coupland asks whether Brian is a believer [in God] to which Brian says he is "genuinely confused" on the issue, aka not sure. However, even before the whole experiment veers out of control, we see him wear a cross thus showing that he isn't as unsure as he implied, plus he is one of the first to suggest that Jane is possessed by an actual demonic presence (a concept I still find ludicrous).

While I admit Coupland's actions were unprofessional at times (like when he hit Jane out of frustration), I think Brian screwed up more times than he did; he allowed his feelings to interfere with his judgment and jumped to all sorts of crazy conclusions. An example of this is when the experiment was really getting out of control, Brian wanted to remove Jane from Coupland's care and get her to a doctor; considering the fact that no doctor would understand how to treat her, this sounds stupid and ill-conceived.

Brian also jumped at the end to save Jane from Coupland when Coupland was doing something that could possibly have cured her; I understand that it was perhaps unethical to tie Brian up as well but considering the fact that he most likely wouldn't have participated in Coupland planned to do, it may have been necessary to save her life. I may be projecting a more caring nature on Coupland than he may actually have possessed, but I feel Brian should at least have given Coupland a chance to prove his experiment. Instead, he saved Jane Harper only to have her kill herself (and Coupland if Brian didn't already do it) anyway. All things considered Coupland's method may have saved Jane's life but Brian in his good-natured attempt to save her ended up causing her own damnation.