Maybe we determine good and bad through a heuristic process that takes into account both systems, making the answer "but it will be bad" not incompatible with logical claims.

Possibly, but ideally in that case, if you asked someone a straightforward question like:

Is there any means by which any number of individuals can delegate to someone else the moral right to do something which none of the individuals have the moral right to do themselves?

Then they would respond by saying something like:

No, there is no way that someone can delegate a right that they do not have, if I am to be entirely consistent. Nevertheless, the consequences are so severe, that we must take this position, even though it's obviously illogical.

And we could go from there. Unfortunately, what normally happens is a negative emotional reaction which makes communication very difficult.

I think your idea about using deontological ethics and consequentialism at different and appropriate times probably deserves a lot of consideration. I suppose in some ways, that is what comes naturally to people.