After which the display was permanently replaced by a copy? ;)
More seriously, though I don't say I believe it, surely it is an interesting point. For example when I visited the Palazzo Barberini in Rome, there were maybe a dozen other visitors total, one musuem worker per ~ 4 halls, and nothing was under glass.
How sure are you of your ability to distinguish the original from an expert fake? The Met's experts apparently couldn't for decades. I'd wager the number of people in the world that can tell a real Carvaggio from an expert forgery number in the double digits.
There are fakes in museums, but those are actual fakes where the museum isn't in the know either. Estimates run as high as 20(!)%.
But a museum that would have an exact duplicate of the art on display for the majority of their art would be incapable of keeping that a secret and likely would not be looked at favorably.
FWIW I was good friends with the ex-curator of the Rijksmuseum in Amsterdam and have visited their vaults, and have been behind the scenes in the Tate Gallery in London. The only thing I've been able to establish with any certainty is that at least those two museums have far more art than they could ever display and that I'd hate to see their insurance bills.
I did not come across an army of master forgers working hard to make new old works or copies of works which I knew were on display.
Actually such a "conspiracy" wouldn't require more than a few to be on it. Why would the guys guarding the spaces, or the people selling tickets and merchandise, the cleaning staff, the canteen workers, the secretaries, etc need to be "on it"? Those are the majority of the "100s" of workers.
Just the director, a few of the people in the administration, the curators, and the ones putting up the paintings (or, actually, not even them).
It's about as likely as a faked moonlanding. But then again, those too have their believers.
So, like 10 people? And even if it was 20 or 100 what's the great rush to expose this? It's just something you don't talk about. It's not even that interesting.
We have crews of 1000s of people not leaking tv series and film plots.
... mounting it in a restaurant? :)
So, restoration rather. Thank you. Too late to edit though.
I don't put much stock in his beliefs.
Therefore they end up protecting it as if it is authentic.
That's an interesting debatable idea, a good kind of idea for a professor to have.
Edit: Is debate important to you?