One of the arguments lying around is that the 5bA is sufficient to anchor the identification in the Landis F3, based on the following reasoning. The mix-cal acetate has an internal standard, 11k-etio, 5bA, and andro, some of which appear in all fractions. Using the pattern matching method, we claim we can see in the Blank F3 which the IS and the 5bA are matching from the mix-cal acetate. We know the blank also has 5aA, so the peak that is in the blank that matches the peak in the Landis F3 must be 5aA, and similarly for the 5bP. Even though we don't have 5aA or 5bP in the calibration standard, we can extrapolate by transitivity through the blank.
This is shown below:
We should note that there are still some open issues about exactly which peak is claimed to be the IS in the Landis F3, because the area is quite cluttered. This is what led WMA to wonder if LNDD decided which one matched by looking at the CIR value of the peak, even though the measured value wasn't entirely within the spec for the CIR of the IS. This adds some lingering uncertainty, because the SOP calls for adjusting things so the IS comes out in the vicinity of 870 seconds, which requires you to know which peak is the IS. If you're off, then later peaks might also be off.
Having claimed to match the IS, and duplicated other conditions, then the aligning peaks in the blank and Landis F3 are taken to be the 5bA.
Now things get transitive. We don't have a standard for the 5aA or 5bP, but we believe they are in the blank. So if we know what they are in the blank, we can similarly match. Let's look at the 5aA first.
The identification is being made in the blank based on the belief that the 5aA follows the 5bA -- see Shackleton, who used the same column, for example. But what about that peak that is slightly after the one we're looking at?
We have a small peak in both samples just beyond the one claimed to be 5aA. Could it be the real 5aA? If so, how would we know? We don't have certainty from a calibration mix of any kind. What we do have is a general idea from Shackleton that the 5aA follows closely, and that it often appears the 5bA is tailing into the start of the 5aA. The argument would be that since we have that kind of tailing from the claimed 5bA into the claimed 5aA, that's what they must be.
Leaving open the question: where does TD2003IDCR talk about proximity and tail shape as identification criteria?
It is also very interesting that LNDD took the CIR of the peak following in the blank, but did not in the Landis. Why would they take one measurement, and not the other, for a peak in the same location in both samples? We see in the blank that peak is less negative than the claimed 5aA, and closer to the value of the claimed 5bA. We know it is trivial to take such a measurement, so why wasn't it made for the Landis?
The same argument arises in the 5bP:
So, there we are. Absent the actual analytes in the mix-cal, we have to extrapolate identities from the blank onto the athlete sample. This isn't a technique specified in TD2003IDCR. The truth of that claim is built on claims that the IS and 5bA were correctly identified in the blank, which leaves us with the previous discussion of the validity of retention times and general pattern matching.
Or, as DailBob notes, the 5bA anchor theory is trying to reach identification by logical argument, not science.