Billionaire investor Robert Smith believes corporate buyouts can be reduced to a formula. His private-equity firm, Vista Equity Partners, has codified that notion into 110 acronym-heavy directives known as Vista Best Practices. They are secret—stored on a company server that makes a record every time anyone downloads or prints them. Target companies must have “critical factors for success,” or CFS, within their control. Employees of acquired companies and candidates for hiring must submit to tests. A personality test aims to determine which of them are suited to which jobs. Salespeople are better off being extroverted, and software developers more introverted………