To Resize Connecting Rods or Not?

it’s not the clamping load that distorts the rod. It’s the criminal press fit of the bolts.
Yeah, no doubt the greater factor involved.
The extra press fit makes the rod/cap interface stronger.
I'd call B.S. on that too... Only with the addition of ring dowells around the bolts or cap screws or (in the case of Gene Fulton, at least) register grooves machined in the cap to rod interfaces.