While it is fascinating, this is a really long-winded and sort of rambling approach to an explanation of how the J58 worked. Even the Wikipedia page does a better job of describing the engine without all the filler of the author's need to type through his "geek out"
What's long-winded is the amount of text that's not actually related to the design and operation of the engine. The information he provided was actually fairly slim but there were a lot of proverbial "oohs and ahhs."
http://en.wikipedia.org/wiki/Pratt_%26_Whitney_J58