Thank you all for your incredible work. And Batbrat thank you for that totally awesome animation. I distinctly remember examining and over-examining the surveillance shots of the per when this first happened. My gut reaction was that is was a woman. A woman with flat feet. A woman who was not in good shape because of the posture and the gait. I remember specifically the surveillance captured image where she/he had her/his hand on his/her hip and appeared to be reading something posted on a bulletin board (or on the wall) It just looked like a woman to me. I don't think someone with MS would have the strength to take on MB. (Someone in this thread mentioned the possibility of MS). However, women with flat feet that are overweight, espeically in their thighs, will walk as this perp did. It's kind of how they balance their extra weight as to not hurt their back.
Anyhow, reviewed the new images as provided by the investigator - still thinking same. Agree with all who think it was a crime of passion. I see a masculine-type woman, overweight - or at least out of shape - with flat feet and a duck gait. Just my thoughts from day 1: the wife or gf or ex of a man that had something to do with MB.