The Linn Westcott book was first printed in the early '80s. I had my copy by at least 1984. It was there where I learned why he picked the name. I had been reading Model Railroader and Railroad Model Craftsman since about 1968, but I also mispronounced it in my mind until reading an article in Model Railroader a while after John's passing in 1973 . That is where I learned it was pronounced as Rich mentioned above.
I might add that John Allen was the Frank Ellison of my formative years.