More questions were asked of Jennifer Coffindaffer, retired FBI. Her answers are below:
What sort of DNA of Bryan's do you think was found at the crime scene: possibly hair, sweat and saliva. He may also have accidentally cut himself while stabbing. Probably wore gloves, so possibly no touch DNA.
Since Bryan was charged with first degree murder, must they prove premeditation? Yes, and the fact that they charged him with first degree murder, it's likely they have a strong case to prove the crime was premeditated.
Was he a serial killer in the making? If guilty, he is a mass murderer. Being able to kill 4 people like this illustrates "complete psychotic dissociation."
LE is very likely doing a deep dive into unsolved crimes in Pennsylvania: unsolved burglaries, missing people, assaults, maybe even homicides. This probably wasn't his first crime.
Do you think he got rid of murder weapon on cross-country trip? Much more likely Bryan buried it or threw it in a river very shortly after the murders.
Do you think we are right that he used a Ka-bar style knife? Yes; it would have helped prevent slippage while stabbing due to the hand guard on the knife. Also, the coroner's report is consistent with this type of weapon.
Do you think Bryan will testify? If Bryan thinks the trial isn't going in his favor, he may have enough arrogance to do a "Hail Mary" and testify, thinking he can save himself.
She thinks this was targeted, a "femicide" murder (Ethan was collateral damage), and that the house was a "soft target". House on a cul-de-sac, great tree line from which Bryan could watch house, lots of people going in and out.