It's not a perfect methodology, but the old “N-of-1” trial is still good for some things. When your dad's brain is at stake and a haphazard "N-of-1" is the only shot you have, you take that shot.
"But Dad is blessed with the oblivious optimism of a man who will unironically wear a fanny pack for any and all occasions, so that never stopped him." This! Love the fact you got him to think it was his idea - the things us women will resort to to get the ball rolling . Best of luck with your father. Wishing you a lot of patience and laughter and long walks with Mannie. My father passed almost 2 years ago. Cherish every moment.