I remember back in the 1990s Gale McMillan ranting on the young internet about the idiocy of barrel break in.

I remember Richard Feynman explaining scientific method and what is a controlled experiment.

I remember a pinned thread on Snipers Hide
https://forum.snipershide.com/threads/objective-research-on-barrel-break-in-procedures.27321/
But in all those pages, I cannot find any controlled experiments.

I know how to work as a consulting engineer and I know how to hire and supervise engineers.
I own zillions of rifles and barrels I put on them from Hart, Lilja, Shilen, Bartlein, Krieger, PacNor, Lothar Walther, Benchmark, etc.
If I were my own boss, I would fire me for not being able to quantitatively demonstrate how Moly is helping or hurting me over the last 16 years.
I would also be fired for a lot of other accuracy related rituals that I can only justify with a hunch.

The trouble is that controlled experiments in accuracy take too much time, money, effort, and skill for the individual.
Even if we did that, individual human beings are not very logical:
https://en.wikipedia.org/wiki/Selection_bias

There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. -Ernest Hemingway
The man who makes no mistakes does not usually make anything.-- Edward John Phelps