Will oil change the applied torque over a dry fastener, yes. (That includes oil under the nut base) and the reason I reduced torque when I did my 850 crankshaft when using Loctite. (Loctite have a recommended % reduction for the product I used to compensate)
I guess it shows it makes little difference on Norton rod bolts (and why stretch instead of torque is more accurate) but the interface between the nut and cap (dry) is involved, not just the threads as far as end torque.
Would the drive chain load pull the bush up against the spindle ?
The swing arm has welded eyes for the bushes.
Those same bushes might be slightly out of round so that can have some input on roundness of the installed bush and spindle alignment. (Luck of the draw)
I did ream finish the bushes on my bike because I had the means to do so, that reamer is only ever used on that type of metal. (not steel etc) It might have taken off a 'poofteenth in one spot.
I would imagine most at home jobs would result in any bind spots should there be any being sanded off.
If you draw in new bushes and the spindle does not slide through nicely what do you do, we know what Mr White does.
Perhaps a book for next year, I wonder if he retorques the four 850 cylinder cap screws over a week period.
I also wonder if they (Mr White and co) were allowed to pick/select parts out at the factory or from the foundries etc and prep or finish machine them outside of the factory production lines.