I've done some reading out of curiosity. My best theory is that there are trailer brakes that are actuated from the 'bicycle' - I think that would make this fea

I've done some reading out of curiosity. My best theory is that there are trailer brakes that are actuated from the 'bicycle' - I think that would make this feasible. But I'm also reading things that make me think I just don't understand the physics of towing, so this might be much more feasible than I initially surmised