In my film journalist days, I was faced with the familiar biographer's dilemma. Except in very enlightened cases, authorised means promoting whatever self image the talent favours, pandering to its vanity by talking only to admiring friends or self-interested hangers on. Unauthorised means write what you want, provided it's not libellous - and your publisher's lawyers should see to that. Ghosted is the third variant, with the talent telling a life story over many intensive days. The ghost transcribes over many more days, structures the material and supplies decent grammar. A pleasure or a pain? My lips are sealed.