I find it really hard to imagine that the crime was personally committed by someone known to H and B. Commissioned yes, committed no. These are soft-handed people. They shoot sporting clays, not deer. I realize that strangulation is often associated with domestic violence murderers, who act in a fit of rage, and serial killers, who want the contact/control with the victim. But I also associate strangulation with certain types of trained killers--Mossad, Special Forces, etc. It is not a quick or quiet death, and it's really hard for me to imagine someone from the Shermans' milieu personally and cold-bloodedly strangling two elderly people on a premeditated basis. But it's easier to envision someone like that commissioning the deaths, scheduling the set-up, and letting a contracted professional into the house. But if that is the case, why is there only one walking man?