I've heard from two people now saying that Audeze addressed somewhere (on their blog?) the inexact repeatability of measuring their headphones on the dummy head they use; and that their graphs were more a general indicator of meeting a performance goal rather than providing an accurate measurement.
There is no problem with this at all. People should not be concerned of the minor variations of each graph that Audeze provides with each headphone. Slight deformations of the ear cushions and partial millimeter differences in placement on the headphone on the dummy head will give slightly different results.
The problem is when people make the wrong conclusion: that headphone measurement systems inherently lack precision or the ability to produce consistent results. This is bullshit.
If the measurer takes the time to precisely align the headphone (using guides, making marks, or even eye-balling), the results should very consistent assuming similar environmental conditions (temperature, air pressure, environmental noise, etc.) Proper measurement technique has more to do with repeatable results than with using Brand X measurement system or Brand Y dummy head.
The following graphs show the results of a Grado SR80 driver measured almost three months apart on 9/13/2011 and 12/4/2011 on the same rig and at the same spot. The measurements below are not exactly the same, but certainly very close. If you look carefully, there is a tiny shift in the frequency of the peaks, probably the result of air pressure differences when the measurements were performed.
While not exactly rigorous or meeting certain statistical standards, these informal "certifications" are run periodically using a small set of headphones on my measurement rig to make sure everything is "calibrated." I'll throw some additional measurements of headphones measured at different times when I get chance. People who have dropped by in-person to get their headphones measured can certainly attest to how consistent my results are.
We'll see as winter sets in.