The author of the blog, Joe Daniels, didn't get it right either, Homer Kelley stated that the ball leaves at PRACTICALLY right angles to the club face. Doesn't mean 100%. From my understanding the statement from Homer in the First Edition Golfing Machine book was just one sentence or a very small part of a section. I also get the feeling Homer understood that his book was just the beginning and the information would continue to evolve.
Anyway, thought the Blog was interesting