The problem at NCL is not "fully laden 747s on a hot day" (get real please) but in fact heavy single aisles such as the A321 in particular when they are trying to get out to Greece, Turkey etc. during summer. The takeoff perf gets very marginal at the 25 end (mainly due to the hill and the line of trees on top of it), sometimes resulting in refuelling stops at MME.
But it would be a very expensive project when perhaps 3-4 movements would actually NEED it per year.