It does sound like a very intriguing idea, and one that I believe requires some research. However, in practice I think this would be equivilent to towing a sma

It does sound like a very intriguing idea, and one that I believe requires some research. However, in practice I think this would be equivilent to towing a small tanker trailer full of chemicals or gasoline. It would require plaques indicating the contents, special insurance, and all kinds of BS at the RMV. Imaging if one decoupled on the highway and drove into oncoming traffic at 60mph? It would essentially be a rolling bomb. This happens quite often with camper trailers. I think engineers would need to emphasize redundancy, failsafe measures, and automated attachment/detachment capability that does not require human interaction to safely accomplish. Then you will convince CA that it doesn't need a ream of paperwork to register and then the rest of the country will adopt it.