I wasn't referring to Jamie (Dimon) either. He's a top level manager, but far from being the type of expert in metals markets that is valued by the institutions I mentioned, and he knows it. He isn't the best, knows it, and that's why he hires the best.
Those are closely held secrets. Do you tell everyone else what coins you search for regularly? Do you tell others how you determine which coins you should be pursuing first and most energetically? Of course not . . . it's counter to your goals. Why would those institutions advertise their most valued resources . . . in fact, while under contract, their intellectual property?
If they are closely held secrets then there is no way to determine that these experts are any better or any worse than the magazine, TV or radio promoters.
Oh, I think we could deduce an awful lot by comparing the average results of such institutions against those of the individuals prodded by the hawkers in the mass media, if only we had that sort of data.