Hello Dave, your concerns are valid. For me, I have never had a rider drop a bike I am selling but I have heard of those who had the mishap. I have sold 27 machines so far and make the call on letting the rider take the bike out based on a few observations:
1. Did they ride their own bike to the showing? If so, that gives me an idea that they do actually know how to ride. If my concerns are eased, they get to test ride.
2. If they did not ride up, did they bring the riding gear expecting to buy the bike? If so, I may be inclined to allow a test ride after talking a bit about their level of experience.
I have not allowed a test ride twice over the years simply because I had no faith they would be successful. I have sold several bike simply after starting the bike or letting them start it and give it a rev or two.
For the bike in question, an America is not a very heavy bike compared to the Rocket. Yet people not accustomed to it may still drop it just picking it up from the kick stand.
In the end, make the best call you can based on each person looking to buy it.
Good luck brother