IT WAS A bitter farewell. On May 25th Luciano Benetton, the 89-year-old eponymous co-founder, with his three siblings, of the maker of colourful jumpers, told Corriere della Sera, an Italian daily, that he would step down as chairman. Signor Luciano, as he is known, explained that he felt “betrayed” by Massimo Renon, the firm’s chief executive. Mr Renon was, in Mr Benetton’s telling, insufficiently transparent about a pre-tax…