My point is not without a good reason. While Kipchoge finally has put the world record too far to almost unreachable level, he is not unwise to forget the two experiences from Berlin 2017 and London 2018 where Guye Adola and Sura Kitata respectively stuck to his heels like glue, giving him the scare of his life. The only solution to this strategy(using others as pacers) by Ethiopians is to produce a sudden surge and maintain it to the end. The sudden surge produces a sudden gap which in effects delinks you from the Ethiopians. If Kipchoge could shift the gears lets say from 4:40 to 4:20 then stablize it at 4:30 for the next 3 or 4 miles, the Ethiopians will be swept by the wind and their confidence gone. That is why I believe Kipchoge will not push the first half but save it for the last half or last 15K of the race. He doesn't want to let it too late also because you never know how fast these guys could be. 21K to 15K are within his strength and can make adjustments depending on what develops during the race. Racing too fast often over the marathon tears up the muscles and will result in immature end to one's career.