Re-read my original post. It has been clear for a long time that the CB came from either contaminated meat or a transfusion. It was not a result of CB doping during the Tour, because it was not present in detectable amounts in Bert's urine except for a two day window. Either of these scenarios, food contamination or transfusion, involve acute rather than chronic ingestion of CB, and would result in the same general findings in a hair test. Probably negative.
So the hair test is scientifically useless here. It might be legally useful, though, because merely by calling for it, Bert's lawyer is setting up a straw man--chronic doping with CB over a period of time--that can be effectively demolished. The two day window has already demolished that argument, but he might want to resurrect it to divert attention from the transfusion scenario.But that will undoubtedly come up, and when it does, the lawyer might, as Python suggested, use passport results to argue that Bert has not been transfusing. As I noted earlier, that argument is also scientifically dubious, but again, might score points in a legal battle.