I think it'll be a long time before 2 hours in an official marathon is broken. It will largly be a solo effort if it is done. Kipchoge and Bekele may be able to push each other but it'll have to be done without pacer for a large portion of the race. Nutrition will only be at stations which normally add a few seconds here and there instead of someone on a bicycle passing it to the runner. The drafting frommthe race also makes a huge difference. I think we will see it, but it'll be a while before we do. I think anyways