They must be marketing for the auto manufacturers!
I posted the following on AutoGuide's site where this article is a few days ago. I expected better from them:
"This article is astoundingly insufficient on discussion about cargo capacity vs. tongue weight. The two passenger rule you quote regarding towing capacity is easily misunderstood. By federal regulation it is not applicable to cargo capacity. Passengers take away from the cargo capacity. For a example a half ton truck may only have 1200 pounds total cargo capacity and by the time you put two passengers in the truck, stuff in the back, the dog, and a trailer with several hundred pounds of tongue weight, you have severely overloaded the truck regardless of it "towing capacity". The limiting factor is highly likely to be cargo capacity. Most manufacturers' towing capacities now are marketing jive and actually are irrelevant when you consider their limited cargo capacity.
In addition, you may also be exceeding the capacity of your receiver hitch on the truck. For example, a half ton truck's class IV receiver is usually more anemic than the big towing capacity the manufacturer's claim will handle from a tongue weight perspective. 15% tongue weight on a 10k pound trailer is 1500#! You have immediately severely exceeded the receiver capacity and the cargo capacity. This article leaves out way too much information for safe towing and the two person rule in the towing capacity is actually quite irrelevant because it is the cargo capacity and receiver capacity (tongue weight) that are the limiting factors. A vehicle that has its suspension overloaded is quite dangerous from a vehicle dynamics viewpoint. "Towing capacity" gets way too much marketing focus and it is a shame for AutoGuide to become an extension of the manufacturers smoke and mirrors (either intentionally or by being naive). Bottomline this article only tells part of the story and is a disservice to the uninformed reader."
"If you must choose between two evils, pick the one you never tried before!"
Southeastern Camping Unit WBCCI #5033