I thought this was a pretty good "TV show investigates a cold case" kind of thing, but I do think it falls into some of the pitfalls that come with Monday morning quarterbacking an old trial like this. Presenting all theories with the same weight is what really got me in the last Darlie episode. When you don't have the firsthand account of the investigators to balance out all these other tangential sources (some who may have been at the trial, but others who just happen to be psychologists with zero connection to Darlie), it starts to feel skewed towards a skeptical perspective.
That's easy to do in this case because we just don't have a ton of information to go off of. Did somebody chloroform Darlie while he killed her sons? Sure, it's possible in that the laws of physics allow for it...but realistically what are the chances that that happened with zero evidence to suggest it? Did some random attacker break in to the Routier home with no weapons even though he intended to kill whomever he found there? It's possible, but that's so exceedingly rare that you have to ask yourself if it's likely. Did some cross-contamination deposit the screen material on the knife in the kitchen, or did one of the parents do it? If this were a standardized test, I'd take choice D -- not enough information to solve.
There are always going to be pieces that don't quite fit in any crime investigation. If you think she's guilty, the the sock is that thing you have to throw out. If you think she's innocent, then most of the evidence presented at trial has to be explained by investigator error. Neither way of looking at it is "wrong"; just different ways of interpreting what's being presented. By the same token, saying that there are pieces that don't fit on its own isn't really enough to say that anything went wrong here. The jury heard these forensic experts at trial, and they heard about the sock, and for them it was enough to convict. Sure, you can say they were totally against her for whatever reason, but I'm not willing to condemn them and say they didn't set that aside when coming up with a verdict.
I really do think she deserves a new trial, only because the birthday party video strikes me as completely immaterial to whether she was guilty of a crime that happened 8 days prior. Good, solid show, though. I'm looking forward to the next case they tackle.