Originally Posted by
roadwarrior
Remember, it's a whole lot easier to ride 27-28mph when you are in the middle of 120 riders. I've coasted at those speeds getting pulled along by the vacuum created by that many riders. Solo rides at 30mph/around 50kph take a long time to learn how to do. You need a big experienced well trained engine.
As Phil Liggett repeatedly states over on the TDF commentary, you expend up to 30% less by being in the peleton. I have not seen the science behind it yet nor do I care.