Thanks for the replies - So it looks like the answers to my questions are
(1) Yes F flights + hotel bargains do exist
(2) There is no easy way to spot which destinations and dates might have good prices except maybe if there is a publicised 'Luxury' promotion or by trying a bit of educated guesswork of where there might be flight capacity in excess of demand.
I would still be grateful if anyone has a better answer to how to find F flight+hotel bargains for someone who is flexible about dates and destinations.