Because many people have discovered that the AKG K550s sound quite different depending on how they are positioned front to back; it's not just about getting a good seal. For instance, people have repeatedly stated that positioning the headband farther forward in a way that is counter intuitive to how most headphones are worn was necessary to get good sound.
So yeah. I would suspect more complicated than you realized, or why make such a statement for a headphone that it is clear that is finicky in fit.
I've read the entire thread. How do you know I haven't tried alternate positioning? The positioning, as described here, is mostly driven by the seal. Yes, very complicated.
Is this for real?