Yet one would expect the governing board of the Bank of Japan to be composed of experienced economists with specialized monetary expertise. How likely is it that any outsider would be able to spot an obvious flaw in their policy?
I think there is a significant chance. Oftentimes, experts may know the truth, but outside forces influence their decisions. An example of that is lobbyists. They often lobby pro their own agenda, which may be quite the opposite of scientific consensus. E.g. think tobacco industry lobbying the government and doctors being opressed for speaking up. This happens in food and health industry all the time too. Scientists that go against the "common knowledge" get shamed and grants are reduced or removed.
I think there is a significant chance. Oftentimes, experts may know the truth, but outside forces influence their decisions. An example of that is lobbyists. They often lobby pro their own agenda, which may be quite the opposite of scientific consensus. E.g. think tobacco industry lobbying the government and doctors being opressed for speaking up. This happens in food and health industry all the time too. Scientists that go against the "common knowledge" get shamed and grants are reduced or removed.