I don't think either is really surprising. 1997 saw the introduction of the 50% hematocrit rule, causing an initial drop in performance.Merckx index said:Yes, but this figures shows a couple of other things that surprise me:
1) The Tour winners in the five years or so preceding LA showed more power on climbs than he did. Indurain? A better climber than LA? Riis? Ullrich, who couldn't stay with LA on climbs when they raced together?
2) There were fewer climbers over 400 watts in the early LA years (through 2002) than in the immediately preceding years. Why would that be? Did the Postal train burn the legs off the climbers before they got to the big hills? Did LA make sure that riders on comparably good programs got found out (Mayo??)?
Then why the large increase beginning in 2003? Just random fluctuations, or the availability of new, non-detectable forms of EPO? Or return to blood transfusions?
The 1998 Tour had the Festina case, that caused a shockwave that still caused waves the next year. A lot of team directors and soigneurs spend quite some time in prison (and French prisons are no joke), I know that at some French teams the DS were searching the luggage of their riders because they sure as hell didn't want to go to jail because one of their idiot riders was caught with EPO.
It's safe to assume that in 1999 EPO use was more something that was done before the Tour, not during the Tour. Of the 200 or so samples that were tested from that year, only 15 or so contained EPO (most from Armstrong himself), while at that point there was no reason to hide EPO use by microdosing (you only had to be sure you were below 50%), giving a strong indiciation that people didn't use mich EPO during that Tour.
2000 saw the introduction of the EPO-test, although it wasn't used during that Tour. We know from the Landis-confessions that Ferrari at this point advised Armstrong to stop using EPO, I'm sure the other big cyclists got the same message from their docters.
It makes sence though that there would be some kind of transition-phase, if you want to use blooddoping, you have to find out when to draw the blood, how to get it to France, how to use it, when to use it etc (there probably wasn't anyone who had used blooddoping for 15 years. Ferrari's early experience with Moser and blooddoping was probably a huge help during this phase). The same for microdosing EPO, they had to learn how much they could savely use etc. Basically after the Festina case and the introduction of the EPO the riders had to re-learn how to beat the system.
A couple of years ago I read an interview with the head of the Lausanne lab, who pretty much confirmed this. 1999 and 2000 saw a big reduction in EPO use, but after that those numbers started to rise. Probably by 2003 Fuentes was active, causing a huge increase in performance of all other athletes. I wouldn't be surprised if the introduction of the CERA-test and the blood passport caused a similair short term drop in performance, untill they learn how to beat those tests.