Great answer Lomcevok & Captain Stable. IRRenewal, yes, I've read the book. Now I am trying to take the learning process from rote memorization to correlation.
Do modern transport jets normally cruise in the realm beyond mach crit where the mach trimmer is doing it's thing (yeah, I know what Davis' book talks about there too). Is mach crit a speed you know as a pilot of your type, and how far back is it from Mmo on any type of aircraft.
Thanks again to all for indulging me.