Steve,
You were the one mentioning an instructor signing off a student for a solo xc to reach the venue for their GFT.
It is not something we would do.
First, we would rather the student to be "fresh" for their test, so en-route weather etc would not be a worry.
Second, how could they then have a beer afterwards!
I think we all agree: no passengers until after paperwork issued.
We may disagree, for an ab initio student, can they be a solo sign-off until then.