The article seems to be mostly about decision making instead of buttressing the claim that diesel cost lives vis-a-vis petrol. It kinda just waves the allegation around without showing any work.

For all I know, diesel is significantly more efficient (maybe like 2x). I can expect to see 50-60 MPG when I rent cars in Europe vs 25-30 MPG when I rent similar sized cars in the US. So that's hard evidence I see every time I drive.