"When the prophet speaks, the debate (for the general membership of the Church as a whole) is over."
I have no problem with that construct, especially since "debate" implies active and public arguing to most people.
"When the prophet speaks, the decision-making process for each and every individual member is over."
I believe strongly that such a construct is incorrect. Each of us must decide whether or not we can accept what is said individually - but, if we truly believe the words are coming from a prophet, we should be very, very careful if we decide to set it aside personally that we are confident the decision to do so is inspired by God.
I have done so myself (chosen to do something contrary to the general counsel given by the prophets), but I have done so rarely and consciously and only as an exception. Also, I think it is critical to distinguish between what is given as counsel ("can, may, should, usually, often, etc.") and what is given as command ("must, will, all, always, etc.). I have found there is relatively little "must" and much "should" and "can" in what we are told - and a whole lot of responsibility for adapting general counsel to our own unique situations.
I still believe, however, that we carry a responsibility to not reject the words of the prophets and apostles automatically and out-of-hand, simply because we initially don't like them. I believe our first obligation is to attempt to understand exactly what is being said, without the interpretive bias inherent in emotional reactions, and do our best to find a way to understand how we can support what is asked - even if only to a relatively small degree or a certain part. If we can't do that and are confident our decision is inspired, fine; that is our right. We simply should give the prophets the benefit of the doubt and make an honest and sincere effort to understand how their words might apply to us.
Knee-jerk, automatic, or hyperbolic rejection is never justified.