Originally Posted by
OldsCOOL
Would the 2mph difference have more impact as total miles-per-ride increases? Sure does for me. (sorry if I dragged this offtopic)
It sure will if you are fatiguing more than the rest of the riders. Once you are riding at threshold power, any increases above threshold require you to burn a match (expression of power spikes above threshold). How many and how long they will burn is a function of your interval training. If you do 10 x 5 minute VO2 Max intervals, you have a lot of matches that can be used. If you do 3 x 3 minute VO2 max intervals, it is less.
As fatigue sets in the ability to produce threshold power decreases and matches shorten in duration and strength. So it is easy to see why riders get dropped so easily. It just takes 30 seconds at 20% more power than an rider can produce to pop him off the back.
The other aspect is skill. Reading the pack and focus on staying in tight formation helps a lot. Any gaps will dramatically increase power requirements on any accelerations or increases in speed by the group.