One thing I don't get. At 600', to be stabilised on approach, the engines should have been above idle thrust. So the statement from the AAIB they failed to respond to an increase in demanded thrust is only half the story. If they continued to provide the level of thrust they were already at before the commanded increase, there's no way they should have landed 1000' short of the start of the runway. Moreover, it appears that No2 was barely rotating when it swallowed a bellyful of LHR's finest turf. I wonder how far out the problems really started, 2nm or quite a bit further?