I have been thinking about this a bit more yesterday while updating the code. I think you are right, we should use only the prefixed values if at least one of them exists. Even I got quite easily confused what setup is actually used when the fields are mixed :-). Randall was also in favour of this approach. So I think we should go this way. I will update the KIP accordingly.
> I'm fine with consistency, but maybe the thing to do here then is to ensure > that we definitely log the "effective" or "derived" config before using it > so there is at least some useful trace of what we actually used that can be > helpful in debugging.