Like everyone has said it pretty much comes down to the discretion of the individual. I keep my CFI certificates current and give occasional BFRs to friends and it is mainly a flight of emergency procedures. I know they can fly safely from A to B and back to A again, they've obviously done it for the last two years. I want to know how they act when the fecal matter impacts the spinning blades.

I do think that doing the flight before the ground was a typical low time move by the CFI, he wanted to make sure that if you busted on the ground he had already gotten to fly with you.