I don't know where that is coming from. What we're talking about in climbers is power to weight ratio. That USUALLY means climbers are smaller riders. But not always. You can be heavy for your size and while you have a great deal of power you don't have the power to keep up with lighter riders. Likewise George Hincapie who I believe was 6'3" was with mountain stage breakaway groups in Grand Tours on a couple of occasions if memory serves. He had to have really slimmed down for these because George was really a sprinter.Taller person = bigger bike = less effort Shorter person = smaller bike = more effort Is this why height = speed?
What we need for a pacer for flat races is a man of normal weight but a lot of endurance. Power and endurance don't normally come in the same package because they are somewhat opposite.
Then there are the sprinters who have to be able to stay in the pack and be led out where they have a higher than normal speed. This requires continuous training. Two years ago I caught myself running yellow lights at 35 mph but now without the continuous training I am lucky to hit 25.
While you can train for an endurance or sprinter, usually you have to be a born climber.
Drugs could accomplish two things - stimulants could get you really going in a race but they cannot give you endurance. Endurance athletes would use several kinds of drugs such as EPO but Lance finally settled more or less on blood transfusions with his own blood to maintain a high hematocrit. This was very difficult to detect.
What did drugs lend to you? Endurance over a LONG race. One day races really aren't much effected by drugs despite what you hear from people that use drugs. Armstrong gained one thing - the ability to continue racing day after day without slowing up. He couldn't climb any better than he could without drugs and he couldn't stay in the pack any better and he sure as hell wasn't much of a sprinter. He was a "cheater" only because of the rules and you couldn't tell because everyone was using them.
However - with the blood passport testing it is extremely difficult to use drugs and they are probably relegated to training.
But the average speeds in the races CONTINUE to go up year after year. This is not because of drugs but from better training methods. And in the case of climbers - lighter bikes.