Here are some personal comments.
I have some questions to raise here in relation to its practical applications. Firstly, it will be outfitted to their cars as of next year so in saying, if you can afford a new car you wouldnt exactly be feeling much of the credit crunch or concerned about driving economically most of the time. Secondly, if you just drive economically from the get go the need of such an item is made comletely redundant & Thirdly, this is coming from a company that produced the Nissan GTR which is just a complete animal and the thought of including that technology in that car is just mind-blowing.
Test Case
In the last year, Jeremy Clarkson made a test using a Toyota Prius and a BMW M5. One is built to be eco-friendly and economical and the other isnt. The test involved the Prius being driven flat out around their test track over 10 laps and Clarkson in the M5 and only had to pace the Prius. The result was that over the 10 laps the M5 was the more fuel efficient and it clearly marked the point that its not What you drive But How you drive. So if you want to save on fuel simply follow a few quick points.
Dont race off from a standstill rather gradually build up the speed, turn off the air-con, brake early and softly, keep a steady constant speed at all times where possibly. Follow that and you'll cut your fuel consumption to that 10% without having to pay an additional 10% on a new priced car in order to save the 10% you could do right now in what ever car your driving.
In closing, I have to hand it to the innovation of the Japanese, by all means not a bad idea as may come handy for drivers that suffer from the leadfooted syndrome.
