I hear it all the time, "Car engines used bushings on the crank."
The only one with which I am familiar enough to comment is the air-cooled VW. Yes, it used a bushed crank. No, it did not feed oil through the bush! It had oil feeds at two places along the crank. And, it was a wet-sump engine. And, if you wanted to rev it past about 4500rpm you had to dowel the crank so it wouldn't beat the bearings to death. Oddly enough, those engines could be built to deliver twice the HP and still be reliable.
BTW: My mid-71 A65 came with the crap-metal oil pump and alloy rod caps. Too little, too late.
There's a tale from Healy in Vintage Bike. They disassembled the first Trident they got at his shop and found casting sand inside the engine. So much for the artisans at Small Heath.
Many blokes are riding their standard setup a65's quite happily, me included, with alley rods and a standard timing side bush. I certainly don't 'baby' my road bikes and i know
the racing outfit i prepped last year (also standard) gets used to 7-7500 often. I really think you suffer from a phobia about beezers. As i've said before, why not just sell it? (and buy another vw)
The artisans at beezer were renowned for 'doing the dirty' on triumphs wherever possible, human nature towards the competition i suppose. Chances are, the blokes at triumph would have done the same.
The bearing used on the a65 timing side is very similar to a car main with the exception of it not being split. Only aftermarket bearings were in fact a bronze bush. Either type work well if
installed correctly. Look at the racing history of bsa during the '50's when they produced the goldie if you need proof they could get a proper production bike to go, it won everything.