Drafting is huge. If the other teams, such as USA are smart, they will tell their guys "Do NOT let a gap open up! If you want a shot at winning, you must never be running with your nose in the wind. Glue yourself to the back of the Kenyans. If you are running one of the first 3 legs and think you can pass them, DON'T! You'll screw whoever you are handing the baton off to. Just stay right on their heels. You don't pass them until 5950 meters into the race." USA should run their fastest guy first to ensure they stay right on them. Once the gap opens it's over.
If Kenya is smart, run Kiprop first and have him totally blitz the first 800, opening up an insurmountable gap. Game over at that point, but Kenya usually runs completely stupid so they'll probably put him last.