I never said it was a good idea and you can ask the designers how it works if you want to know (btw it's probably the same way other automated braking systems work that many modern cars already have).

But not needing a big truck to tow would be a benefit whether you like it or not.

Tow lights connectors aren't magic. Any car can be outfitted for electronic braking and turn signals super, super cheaply. You literally splice into the wires going to the tail-lights. Then you have signals for the turn indicators, brakes, and hazard lights.

I rigged my vehicle for lights and brakes on a trailer for like 12 bucks.