EPO has been used in elite cycling since the late 1980's. In fact, at the time is was discovered as the ultimate endurance enhancement, the levels used by cyclists must have been obscene. I have read reports that during that time over 60 European cyclists dropped dead of cardiac arrest due to blood clots. I guess they were the first guinea pigs as to what levels are too much for the human body.
I am a bit curious about the recent Moroccan athletes busted for apparant use of EPO. I would think their pharmacists are skilled enough to know what amounts would be needed and still stay under the radar - or the science of this form of blood doping is still not perfected.
I was curious as to any major road races in the U.S. that test for high levels of red blood cells. I would suspect few to none.