The genesis of my range question goes back 35 years: A F/E at KLM theorized the DC-10 was "hobbled" by the nose-down moment of the high #2 engine, causing excess stab trim drag. He proposed running #2 at reduced thrust in cruise to lessen trim drag.
He would have been correct, too, if it weren't for the unfortunate fact that engine SFC deteriorates with the reduced thrust, thus eating up any gains in trim drag.
