Derek,
I have seen x-rays of "aligned" clients who had surgery and they were not aligned at the symphysis pubis joint and not aligned in the transverse plane. Tops of iliac crests appear to be symmetrical. a huge problem is the fact that the body can cause asymmetry of the pelvis from joints in the spine, hip, knee, the 26 bones in foot and ankle, all the musculature, even asymmetry of shoulders can pulll on a muscle that connects the shoulder to the ilium; latissimus dorsi.
Research on x-rays covered in my torsion chapter briefly, positional artifact can affect some of the alignment. Some clients have a developmental asymmetry of the hemipelvis and this can be readily discerned. I am much more concerned about maximizing joint function than "alignment". Asymmetry, visual malalignment guides me to do passive joint testing to confirm or negate possibilities.
Several pelvic asymmetries look very similar, so the passive mobility testing and ligament testing is crucial to discern. Further there are advanced patterns that are not taught to Physical Therapists, that PT's cannot find with the traditional testing. It is what it is. It is far more comnplex than what is being propounded, but fortunately for the majority, the presentation is fairly typical such as the Most Common Pattern. If interested in more you can find more at the Hesch Institute web site. Snake oil or purple kool aide $$$ dunno but we can be much more thorough in testing and treating and much more honest in the information we give to desperate clients. It is a choice we (as clinicians) can make.