What do Sam Altman and David Sacks have in common? Certainly not politics. Mr Altman, co-founder of OpenAI, is part of the transition team of Daniel Lurie, the Democratic mayor-elect of San Francisco. David Sacks, an entrepreneur and polemical right-wing podcaster, will on January 20th become Donald Trump’s crypto and artificial-intelligence (AI) tsar. Yet both have the distinction of being among Silicon Valley’s best spotters of entrepreneurial talent. According to data from TRAC, a venture-capital (VC) firm, few are as good at picking promising startups at the very earliest stage.