...you then have to come out with better proof to state that the factory race dept was doing haphazard and arbitrary things...
But but but-- is it not you own website that publishes the Jesse OBrian story, brother of the race manager at Harley in those early years? He made it sound pretty haphazard to me. So did Jerry Branch when he told me how he begged the race group to dyno a set of cast iron heads he welded with with his small-ports flat-piston theory. After nine months they did finally do it can called him asking for 20 sets.
This in no way is meant to trash the great reputation of the race group. Branch also told me how the XR-1000 was a gauntlet thrown down by the race group when they objected to Porsche designing the Evo motor. According to Jerry, the production guys said "If you guys can design an aluminum head in 9 months, go right ahead." That's exactly what the race guys did. It is a shame that corporate group-think made the XR-1000 an option instead of the standard 1983 head, and that they killed it instead of letting the Porsche design be only for big-bikes.
I'm just saying we can only guess what was going through their minds, or what they were building, but I gladly concede that experts like you are far more "in their heads" than anyone else before or since. I will say that it sure looks like Harley engineering and documentation would be laughed out of Detroit, based on my working at GMC Truck and Ford. Dave Hennessy gave a great insight when he commented how broke Harley was in 1950s. The 1950s are when Indian went under, after all. And so Harley would weld up frames or slap last-years parts on bikes if it was cheaper. We can guess what they were doing, but they never bothered to write a lot down. If Harley would release the ECOs (engineering change orders) we could see why the did things, but many of them might say "cost reduction" like when I was in the auto business, and they would be rightfully embarrassed.