But you don't need the lanes to go 100mph - during the morning traffic jams, they could just go 100kph (or ~60mph), taking a tenth the time and half the normal fuel consumption of a commute.

Once that happens, you can be damn sure that every new car purchase by someone that commutes will have the system.

So while you may be right that 100mph lanes aren't a good idea, the idea has a lot of merit.