"And again, even if the pedestal is wired as a sub-panel (i.e. the ground and neutral are not bonded), and the neutral and ground are crossed, I still fail to see the potential for a dangerous condition... "
Read my post several pages ago. Read the part about the coax getting hot!! This is due to the difference in voltage between the hot and the neutral under load. The coax now shares the return current and heats up. If there is a bad connection on the coax like maybe only a few strands connected and it is in the wall somewhere it could cause a fire.
I had one experience in a campground where the neutral and ground were reversed. This is how I found that there was a problem. After plugging into a 30A circuit all seemed OK. Everything worked as expected. Next I connected the coax for cable TV. When I connected it I saw a small spark! After a short time the cable got warm. After thinking about this I realized that there must be current on the ground wire in the campground. There will always be a voltage drop on the neutral wire if there is any load on the system. There should never be a voltage drop on the ground wire. Connecting the coax from the camper to the cable outlet at the campground connected the ground wire in the camper to the ground at the campground post. If the neutral and ground were reversed there would be current on the campground ground wire causing a voltage drop. This voltage drop would be seen from the camper ground to the campground post and drive a current in the coax cable. It would be a small voltage maybe a few volts but the current could be vary high.
So one way to tell if the neutral and ground are reversed you need to measure the voltage from the campground ground wire to a good ground like maybe a water pipe. Another way might be by measuring the current on the cable coax, it should be 0.