Well, I never. I joined this string when it had grown to page 4. I even started reading from page 1. But then I skipped to page 4 and to discover we are still on the same topic (although there were a few attempts to divert the discussion
Many of the points made about the pressure under the disc reducing the induced airflow, as seen on a vector diagram of the airflows and forces acting on a rotor blade were agreeable to me.
However, when I did my Instructor rating a few years ago, a wise old instructor once taught me:
I.F.O.I.T.A.
Does this ring any bells with anyone?
Just
DOINMABEST