What happens if the training flight was actually three flights
You need to re read the regulation. ALL of the revalidation requirements need to be met before the licence can be signed. That means if it's split over more than one flight it is signed after the final flight that completes the requirements.......
Now I refer you back to my comment about the differences between examiners and authorising an Instructor to do a limited Licencing action on behalf of the authority......
I have read the regulations. The point I was making about the three flights is that two of these could have been 11 months ago. Apparently I can be trusted to recognise my own signature on these flights, but not if it was a single 1 hour flight yesterday. Where is the logic there?
I have re-read your comments about the differences between examiners and instructors, but I'm afraid I don't see anything there that explains how it is better for an examiner to verify the qualifications of a potentially unknown FI than for the FI himself to recognise his own log book entry and signature on a past flight.