The difference lies within the world also. Despite the claim that "marshalling yards" were just an American euphenism for terror bombing, it is a fact that the Reichsbahn was in ruins by the end of war, deprieved of its rolling stock; as were the German oil industry.
And it wasn't a mysterious fairy that did it, it was USAAF and its bombers and leaders who pushed for it
Whilst it was the Americans who pushed most for the oil campaign, the transport campaign was the brainchild of the RAF's Solly Zuckerman. Both the 8th AF and Bomber Command contributed to the oil and transportation plans.
Nobody is denying the 8th AF also genuinely targeted German transportation targets. The point Davis is making is that when the 8th were going after a particular rail target they did so visually using HE. When they were conducting an area raid they usually did so using radar aiming and a large proportion of incendiaries, and claimed the target was a "marshalling yard".