schlep1967 wrote:
...had the driver get in and back the truck up against the pin...
You touched on another reason to chock. I also have one of those hitches with the Chinese finger design, and if you aren't pushing rearward on the pin it will fight you when releasing. Actually took me a few trips to figure that out on my own. Now I often travel alone, so I've learned to chock, put the truck in reverse, and get out and release the jaws, then jump back in the cab. Not something you would want to do without chocks in place.
I've witnessed people hammering on their release lever, apparently not having learned that lesson.