Thanks again for responses. I would like to ask ORRISMA if he would agree with my following interpretation.
On the forward cast the pull portion of the line-hand haul ,with the correct timing and duration, should overcome the kinetic energy possessed by the line.
This will result in the rod starting to lose its potential energy (begin to straighten or unload ) but before this can happen the line release portion of the haul is initiated and the increased kinetic energy of the line and fly is RE-APPLIED
This results in a further loading/bending of the rod that now has increased potential energy than before the haul.
The abrupt stop of the rod immediately following the haul release will result in the normal perfect tight loop but with the added benefit of distance and force to combat a headwind.
So am I correct in saying that the reason the rod bends further after a haul is due to a second application of the lines kinetic energy brought about by the release portion of the haul/tug by the line hand causing the rod to bend further ?
Your hoped for response is "by George he has got it" spoken in a perfect John Cleese accent; of course it could also be "the man is an idiot -sell him a parrot-"