Doesn't seem like it's your decision then.
This is absolutely the WORST advice I've ever heard with regard to the operation of an airliner.
This is the same thing as saying that the captain has the final say on busting minimums on an approach, disregarding W&B, ignoring duty time regs; you name the bad idea, if it's the captain's (dispatcher's, company's, or even flight attendant's) final word, you have to go along with it as a First Officer. WRONG. WRONG. WRONG.
Above all, if the Captain, who is both the legal and correct PIC for flight, (read: not the FO), makes a decision that is in accordance with part 121, or 91 if appropriate, that is per the FOM and OM, and makes plain good sense, it is your job and duty to support that captain and be a professional in every way. Within these paramaters, if you, as an FO, intentionally choose not to support that captain, you are more dangerous than the captain who makes poor decisions.
All that being said, it is your job to speak up when you perceive a safety, regulation, or procedural issue. If you speak up about a valid safety issue, and are ignored, it is your job as an FO to prevent an accident. If that takes refusing a flight, so be it.
If I were to receive company discipline for refusing such a situation, it would get ugly. First off, I'd have a chat with the chief pilot and attempt to resolve the situation peacefully. If that failed, then it would be time to have a chat with the safety reps for what ever collective bargaining entity I would be affiliated with at the time. Barring that, welll, there's a good reason that KATL is within sight of the Atlanta FSDO.
Bottom line, FOs support valid orders from Captains. If any of the
three parts of that statement are in disagreement, do what ever it takes to prevent an accident.
(Extra credit: Without searching, can anyone define an accident in the eyes of the NTSB?)