Not sure if others have seen the clip but I recently saw that Warren Buffett’s returns pre-Reg FD were beating the market by roughly 10%/year. Then Reg FD happened and since then he averaged roughly market returns.

Obviously portfolio size is also a big driver here but, given how much he talks about just calling up management in the early days, it’s hard not to wonder if we’re underestimating the impact of limitations on public disclosure.