"If the AFM permits 15 kt tailwind then why not utilise that facility which gives flexibility and has commercial merit"
Maybe because some companies are downright dangerous in still wind not to mention a tailwind?
My previous employer is a good "case in point" with the number of "long landings" ie. greater than 1/3 of the runway or an extremely long (but can't remember? 12, 14, 16) seconds in the flare to trigger a FOQUA!
