At this point in his life, it seems meaningless to debate whether he's still a good investor. He won't have to live with the consequences of today's choices in twenty years. Neither money nor anything else can benefit him. With no incentives, it doesn't even matter if his ability is intact. In twenty years, his successors will either have run BRK into the ground or overshadowed him and nobody will look back to his final investments. Which he must know.