It does seem incredible. I guess we will be hearing more specifics about the "direction" of the investigation during future LE interviews -- although my guess is that these may slow down following the release of this PCA. How they did not find some way of zeroing in on RA with this much evidence -- even to working out who owned a gun that might have matched this cartridge -- is beyond me.
These docs do confirm for me the absolute horror of the crime -- walking with purpose, showing the gun, forcing the girls down the hill, the murders, then emerging from the scene "muddy and bloody" and going on with his life -- for more than 5 years.
This is a bleak, bleak day.