This is what I can't get around - at minimum we are talking 4 shots at either location to kill the 2 people there, which would have been heard in the other location. It seems either Chris or Frankie had to be subdued or already dead, if they weren't killed at the same time. That I think is where we get the "sophisticated" part of this crime - it also indicates this was not a crime of passion or a drug-fueled craze.
The other thing that strikes me is that the coroner referenced soft tissue injuries, which either indicate fighting back or beating up (i.e. torture). BJM said someone had beat the "f--k" out of CR Sr. & GR on the phone - there was blood all over the place. It sure sounds like they put up a fight, at least. It wouldn't surprise me if Frankie's was the same.
I've been catching up on all the forums here - appreciate that there are people as obsessed with this crime as me.