I'm sure he was a fine pianist, but he was also mind-bogglingly offensive. Here's what Hofmann had to say about "rag time" piano:
"The touch with vulgarity can never be but hurtful, whatever form vulgarity may assume -- whether it be literature, a person, or a piece of music. Why share the musical food of those who are, be it by breeding or circumstance, debarred from anything better? The vulgar impulse which generated rag-time cannot arouse a nobel impulse in response any more than 'dime novels' can awaken the instincts of gentlemanliness or ladyship. If we watch the street-sweeper we are liable to get dusty. But remember that the dust on the mind and soul is not so easily removed as the dust on our clothes."
There are better books on this subject, to be sure.