I'm not an instructor, I do have 20 years flying experience, much of it flying with some of the most experienced pilots in the world. I do (A) and (B) on every flight; occasionally I may use memory, but I'll do them nonetheless: out loud if there's somebody else in the aeroplane.
If I fly with somebody hoping to join an aircraft syndicate who don't do these things, then I'm likely to refer them for some remedial instruction before they come back.
If I flew with an instructor who didn't do these things, then I'd not fly with that school again - they clearly have low standards that I don't want to go near.
Obviously however, most trial flight students don't have the ability to make this judgment. But all instructors have the ability to fly properly and procedurally.
G