Any books on vacuum advance and timing???????

True enough. I figure that if someone went through all the time and expense of publishing and distributing an actual physical book, is able to sell them, goes through a couple of editions and /or printings, they have a little more credibility than anyone who knows how to post something online. Sometimes.

You are certainly right about that.
Problem is, the people with all the varying opinions did exactly that. :D

Now I'm just being a PIA. :D
Google knows everything there is to know, it's a matter of filtering sources and cross checking.