Well-proportioned, versatile, aesthetic, durable - the English Electric Class 37, the great survivor of the modernisation-plan diesel fleet, deserves all of these accolades and more. Never as celebrated as the Deltics, never as idolised as the Westerns, always intended to be a workhorse; this is the locomotive that has, in many ways, surpassed its more illustrious peers as an example of all that i...