Listen, Buffett has nothing to hide. There are many, including myself, believe one of the T&T made the initial Apple call. Of course, Buffett has gravitas to take it to the level. However, how would you value that? Moreover T&T responsibilities have evolved, they are no longer just money managers.
I simply assume WEB is the greatest investor and he benefitted from lot of things including lower equity valuation when he started. You are not going to find another Buffett. So drop that bar. You can assume some discount to Berkshire equity performance and move on.
I really don’t see what exact benefit to the shareholder knowing how their picks did compared to S&P. Do you know how various subsidiaries are performing vis-à-vis to their industry peers?