Hello Edd,
you’re right saying that some functions (for example the gear shifting) cannot be checked properly without load,
of course were wheels, brakes, gearing and other important functions checked by my friend while riding the bike over a small distance at his in-house backyard.
But for my meaning is a real test ride different to the short adjusting run mentioned above.
What I call a test ride should happen onroad and offroad, during several kilometres and (best) for a few hours.
I think nobody would accept a bike for 2000 Euros, which was ridden before by many users for a long distance.
It should be also mentioned that Mike usually does not sell bikes via the web, he is used to explain and/or adjust every bike together to/with the customer.