Are trains environmentally friendly?

"I know this will generate howls of protest, but at present a family of four going by car is about as environmentally friendly as you can get."

Can this be true?

They [researchers] calculate that expresses between London and Edinburgh consume slightly more fuel per seat (the equivalent of 11.5 litres) than a modern diesel-powered car making the same journey.

It gets even less politically correct:

Roger Ford, of Modern Railways magazine, said one reason for declining energy efficiency [of trains] was the impact of health and safety and disability access regulations.

Here is a relevant Telegraph article. Here is David Nishimura's post, my source on this matter. Here is the researcher's home page. Here is The Transport Blog, perhaps they will offer comment.

N.B.: I have not seen the underlying data, and cannot find the study on the web. In the meantime, for some further revisionism, read Eugene Volokh on the myths of the Cuyahoga River Fire.