Ken, do you not think that the ops/crew would have looked at other options before going for the pax offload?
Offload non-essential freight/gear?
Burn some extra taxi fuel to get below MTOW?
Double-check all the weight, fuel, performance figures?
I myself have decided to turn and burn for an extra ~15 mins rather than dump gear- I ended up a little late but the powers that be were happy with my justification for the delay and burning some excess juice.
Planning for the unplanned is sometimes quite difficult!
I'm also pretty sure that not 100% of the passengers on ANY flight "HAVE" to get to their destination- there are always some that could probably go on another flight and be happy with a freebie ticket in return. Maybe there were people on board this particular flight that were too selfish to volunteer to jump off which in turn played a part in "stuffing up the holiday plans of a couple of innocent punters."