Some of the posters on these threads want to apply federal commercial towing regulations to recreational towing.
They attempt to do it regarding brakes, propane, speed, safety chains and weight. I suspect some of them are or have been commercial truck drivers and think the regulations that applied to them when they were driving commercial 18 wheelers also apply to recreational towing.
Recreational and commercial towing have similarities but they also have differences. As far as I know, there are no federal regulations that apply to recreational towing simply because recreational towing does not fall under federal jurisdiction. You know, that 10th amendment and all that constitutional stuff.