There's a project that has been going on for a few years now testing the idea of road trains to solve traffic problems. Whilst Google and others go on about driverless cars, Volvo instead think the answer is 'platooning'. Their idea is that trained drivers in lead vehicles set up the head of a road train, and if your car is suitably equipped, you can join the end of the train and your car goes into a self-drive mode, taking its cues from the lead vehicle. As with many ideas before it, Volvo claim this will reduce congestion, reduce fuel economy and increase speeds. And as with many ideas before it, it will fail for a number of reasons.
First - the trained driver. We are such a litigious society now that this concept alone will be the reason this system will fail. Volvo explain that the lead drivers would be licensed, insured and trained but even then you're asking the other drivers to put their vehicle in the hands of someone else whilst they sit back and do nothing. What happens when the first of these systems crashes, or the lead driver is drunk or high? The lead driver is human, and will suffer from everyday human frailties just like you or I. And who is going to pay these lead drivers? Whoever pays them becomes liable for any accident involving the vehicles following them.
Secondly, the infrastructure. As with all these systems, it will require an infrastructure change. In this case it will require all cars to be fitted with hardware and software to allow them to work in the road train. That will push the cost up and people will opt not to buy it. That assumes that the vehicle manufacturers could even agree on a single common standard, and history has taught us that this will never happen.
The idea that any driver would want this seems laughable to me. If you want to cluster a bunch of people together in tight formation behind a single driver, get on a bus. It takes up a lot less room on the road than 50 cars and it works right now. If you really think driving a car should be trivialised to the point of it being a self-driven "capsule" that eliminates the driver from all responsibility, I don't want to be anywhere near you on the road.
Volvo explains why road trains are the future