It’s an interesting question. They were certainly independent thinkers and had many well publicised differences in stock picks that we know about.

Warren wouldn’t buy Costco.

Warren sold Wells Fargo but Charlie was happy to tolerate a little bad behaviour.

Warren reluctantly allowed the BYD purchase.

Charlie thought Warren tinkered too much around the edges on things that made little difference like the square negative yield bonds.

Charlie struck me as more of a deep roller and risk taker and Warren a little more prudent.

But probably 99% in agreement most of the time. An incredible double filter that sidestepped so much trouble and setbacks.

Must have been a really hard year for Warren without Charlie. Perhaps unrelated but Berkshire has become more prudent in the last year. Maybe not unrelated. We will never know. Sandy Gottesman has previously commented on Berkshire - post Buffett - might take a little more risk. Again probably won’t be that different.

Certainly, in hindsight I’m glad Warren didn’t take out a margin loan to load up on Alibaba at 20 times earnings. But equally, $100 Bullion Costco gain would have been good.

Together they bought Apple, BYD, Sees, GEICO, Coca-Cola, built the world’s greatest insurance group and one or two other achievements! So I guess they were essentially like two peas from the same pod.