The Signal InterviewWhen Bruce Van Saun was asked in 2013 to become CEO of Citizens Financial Group, he recalls, the US super-regional bank was “a little orphan runt” with returns on equity that were roughly half those of its peers.Citizens at the time was an offshoot of Royal Bank of Scotland, where Van Saun served as finance director through a turbulent few years after the global financial crisis. The American-born banker seized the chance to …