Dallas_, first of all, i'd like to say (also in a friendly manner) that you cannot engage objectively in a discussion about Valverde while using the name "valv.piti".

Concerning the BP, i'm not an expert in this matter, but I what I know is that it's a longitudinal follow-up of blood values of cyclists to detect the abnormal fluctuations, however it does not tell you of the cause of these fluctuations, even when combined with other data related to the rider (substance control, other medications, illnesses) and i think there lie the weaknesses of this system and adds more controversies and uncertainties to the situation.
As for the other points, Libertine Seguros has answered them.
Valverde being consistently on the podium from 2006 to 2010, and his suspected links with OP, was one of the most closely watched and monitored cyclist so I think that P(being doped after 2006) <= P(Being doped before 2006)
As for everyone being doped, I was really assuming that and don't have any concrete evidence for it but we all know that there are many ways to be doped and get away with it, even with the BP, extensive testing, etc