Maybe all of the show is some grand retelling from Don in old age, looking back with regret on all the wrongs he never had the chance to right. Maybe hes telling it to Sally and Bobby (and poor Eugene, who everyone - especially Don - seems to forget about), in a final hope of reconciliation before he passes away. Maybe he just really wants to sleep with their Aunt Robin, who knows? That said, there may not be much interest in seeing Don Draper - suave, sexy sleaze ball that he is - as an old man. Unless he grows an epic Roger Sterling-esque moustache, of course. An alternative to this is that it could be Sally who is regaling the tales of her father, either an older version or a seriously stoned-at-Woodstock one (an event she would be quite likely to attend, given what weve seen of the character and the year of the show), which would explain why so much of Dons life - especially when it comes to his children - is painted in such a negative light.