Thanks to Road Bike Rider. They have a great news letter. Here are some interesing factoids I learned. It explains how the pros can travel at 25 mph for days on end. Of course they produce twice the wattage (200 watts for a mortal vs. 400 watts for a pro), but being in a big pack helps quite a bit as shown below.
Remember, the area behind a cyclist is a low-pressure area.
When someone passes you, jump in behind them and ride in
their low-density space.
The benefit is more noticeable the closer you ride to the
cyclist in front. Racers must learn to ride comfortably
within 6 to 10 inches of a back wheel.
Wheel Gap / Decrease in Wind Resistance
3.0 ft. = -34%
2.0 ft. = -38%
1.0 ft. = -42%
0.5 ft. = -44%
Wow, you reduce drag by 44% when you are six inches away from someone. What a huge reduction. So, I only need to draft behind Hoops and I'm set!