Prior to my retirement (in 2008) The B757/767 QRH had no provision for inability to restart either engine after both had failed. Is that still the case? Although not a requirement for rating renewal I would occasionally suggest to crews in the sim that they might like to practise dead stick landings just for the experience. I added a section in
'How To Do Well In The Sim' to give some guidance but this input was never 'official' and I'm not sure of its efficacy.