The guy did poorly the day before the test, blew 'em out the day of the test.

The normal testosterone-epitestosterone ratio is 1-1. The allowable is up to 4-1, over that is considered a "positive" test FOR doping. I don't know what "normal" variability is, could be high, but 4X normal is seems pretty high. Wonder how far over that he was. They seem pretty sure.

Landis gives positive drugs test

"Landis finished ahead of Oscar Pereiro to win the Tour de France"

"Tour de France winner Floyd Landis has given a positive drugs test, his Phonak team revealed.
The 30-year-old American, who claimed Tour de France victory on Sunday, has tested positive for excess levels of the male sex hormone testosterone.

"The positive test came after stage 17 of the Tour, which saw Landis record an epic victory after struggling on the final climb the day before."

Another reference to levels -

(Most people have a ratio of between 1.5-2:1, but the limit - like the blood hematocrit limit of 50 percent - is 4:1 (for men) to allow for those with naturally high testosterone levels. If it's greater than this level, then it's considered a positive unless an athlete can prove that he is always this high.)

Arf