Honestly if he had asked for my consent, I might have thought about letting him brand my organ, it's not like anyone will see it or care. It might mean he takes more pride in his work and thus do a better job.

I understand a professional wanting to "sign off" on their work; programmers, scientists, artists, engineers and so forth really like putting their name on things so why not doctors?

If he were forthcoming maybe only 10% of patients might agree to it, but that should probably be enough to scratch some egotistic itch.