Lu,
I feel we are suffering from a trans-Atlantic terminology problem. In the UK Military, the term “Control Rigging Angle” is used to define the angular offset of the Servo Jacks and “Advance Angle” is used to define the angle between the blade axis and the pitch change rods, which together will equal the “phase lag”.
Coning angle is only one part of “flapping to equality” and was addressed in one of my previous posts (the one with the “mathematical gibberish” as you put it).
My last post was explaining how I teach a basic student, so for instructional purposes we use 90deg; it is a little simplistic. My previous posts have been aimed at a higher level.
Quite a while ago, I spent 5 months at the Central Flying School (Helicopters) on the instructors’ course. Since then, I have successfully instructed UK, US, French, German and Danish aircrew. The syllabus and techniques used have been quite successful for many years and produce some exceedingly capable pilots, who have no trouble understanding the concepts in my last post (I would add that that lesson takes about an hour). I agree that simplicity is good for instruction but one should never fudge or mislead a student. If a student doesn’t understand one must ask simply explain how it affects them and leave technical understanding until later.
I have the utmost respect for your experience and knowledge but I would suggest that we let the subject lie as we are not going to agree.
Grey Area
(Perhaps some UK Military trained chaps might want to comment?)