I am not (and have never pretended to be) an expert on doping. But I am professionally immersed in debates about how confident scientists should be, and how confident they say they are, in their own data. Arguments based on "we can't see any other explanation for these findings" should always be treated with suspicion because scientists almost always subconsciously downplay the likelihood of alternative explanations they haven't thought of. To say "this sequence of haematocrit readings is compatible with doping" seems true. To say "it is hard to think of any alternative explanation" is probably also fair. To say "this therefore suggests doping took place" is also fair comment - except that it almost certainly doesn't suggest it as strongly as the person saying that means. That, sadly, is the human nature as applied to scientists, and I speak as one myself.
I guess this comes back to the level of proof required. IF the test were "beyond reasonable doubt" (which we all know is not the case for USADA) then there would have to be a lot of debate about whether "we can't think of any alternative explanation" applied to these blood tests would be good enough (though I repeat I am not an expert in either the lay or court senses, so I can't really judge how strong this particular piece of evidence is, it's just my hunch). If the test were "balance of probabilities" it probably would be good enough. As I understand it, the USADA test is somewhere between those two.
(and of course, those of us who are simply trying to make our best assessment of the truth, rather than to follow USADA procedures, don't judge these data in isolation - if we have other reasons for suspecting LA of doping, that quite legitimately alters our assessment of the relative likelihood of the doping versus no doping alternative explanations.)
