Note (March 2010). This is not as POV as it might appear. At the time there was considerable correspondence in Locopmotive Express and also in Railway Observer; O S Nock also makes a passing refrence in an article in The Engineer. This 1950s correspondence was summarised in an article in British railways Illustrated magazine (published Sept 1996) which was reproduced in The Book of The Britannia Pacifics, Irwell Press, 2004. I will compile these refrences and add them to the article ASAP