Twiglet, I can tell you that our pairings to Middle East and India with 18-30 hours rest blocks (mostly approx 24 hours) are impossible to rest for on the second sector.
Our departures ex-HKG have us landing early morning body clock time and in bed around 3 to 4 am on average. With 2 night's sleep to be achieved in that hotel period, and with call times around 10 to 11 pm HKG body clock time it is absolutely impossible. At best you will get a good solid sleep after landing, and a 2 to 3 hour nap before call.
You are clearly CX management. If you genuinely thought it was a good pairing, you would give everyone a sleep monitor watch and prove yourself correct. (Ha!)