That last post of mine was sorta "ex cathedra." Company position on oils for use in APUs. Personally, I'm less picky.
I used Mobil 1 exclusively in my Bronco and it used no oil to 193,000 miles, when it was destroyed by a girl (a model - OK, I'm a sucker for pretty girls) I'd loaned it to.
I used Mobil 1 in my KLR and found that the bike consumed twice the oil as when I ran a petroleum 10W-40 oil, so I switched to whatever the cheapest is at the truckstop. That bike, a big single, uses at 30,000 mile the same as it used new.
I'm using Honda oil in the VFR because oil change intervals are so long, and it's really only used on long rides, that I can stop by the shop and pick up a gallon without interfering with my riding. It uses no oil at 15,000 miles. Zero.
If I raced, and I don't, I would pay attention to claims of additional horsepower and weigh the risk to the engine in terms of winning. One thing's for sure - there is a cost to any benefit. I'm a street rider and the 620 isn't going to turn into a Hayabusa by using a different oil. If I wanted power, I'd have bought a different bike.
Personally, I believe the most important thing is not which oil, but that there's enough. They're all good. If the clutch is slipping, change to something else. If it's cold, go thinner. Multi-weights do get the oil to the bearings faster when it's cold. And an engine that never cools down will last forever.
Back to APUs. We schedule overhauls based on cycles, not hours. The cold-hot-cold cycle limits wheel life due to thermal stresses, but a similar argument could be made for lubrication and condensation in the oil. A bike running at 100mph continuously all day long will last way longer than a bike cooling and heating and riding in lower gears.
We've got a tribologist here at the company. Kinda like the Maytag Repairman. Once we, and the military, decided on oil, nothing was left to be done. He's now specializing in gear design, so he has something to do.