The difference between the two of us: You are the number crunching guy, and while I am usually that too, here I am the psychology/sentiment guy - - - and interestingly both are currently going in the same direction, more or less: You don't say the market might tank any time soon, just that one should expect only meagre returns from here, for the market in general and for Berkshire too.

In the end this means the same I see: That the risk-return ratio is much more unfavorable now than it was say 3 years ago, that the risk now is high but the potential reward of being fully invested is low.

That of course can be dismissed if one intends to sit on both, the market and Berkshire, for many years to come and has no psychological problems to sit out years of no returns or even a crash, but otherwise....