I've been a long- time reader here, but just registered recently. I hope I'm posting in the proper box and not messing with anyone's post.
After following the discussion from the beginning I feel like I want to put my own theory "out there".
I think that this man planned these murders. I think he was dressed in clothes that hid what he normally wore, by adding more clothes over the top of his regular clothes. I think he had bags with him to put his outer clothes in after he commited these murders. He has himself covered enough to not leave any evidence behind, and by placing his outer clothing and shoe covers in the bags, he was also not going to take any evidence from the murder location back home with him. I believe he knew these girls, either by his being a coach, a teacher, a janitor, a neighbor, whatever, but he knew these girls and found out by overhearing about their outing and walking on the bridge that day and time, or he found out on social media. I think the girls may have somehow set him off with innocent remarks, giggles, or really any typical teenaged girl behaviors. This person obviously has psychological issues , and possibly he fixated on these two and made plans for their murders. I believe the girls recognized this man and didn't realize who he was until he got very close to them. After the murders he walked away to his vehicle, removed his outer clothing and shoe covers , put these items along with any weapon he may have used in the bags, then disposed of all the extra clothing , weapon, and evidence of being in the woods before he went home.
I have two daughters. As parents , we are always warning our kids about "stranger danger", don't talk to strangers, run, fight, scream. These were 2 very smart girls. If they knew this man they would possibly be less wary of him, or possibly too intimidated by who he was in their lives to not do what he said. ("Go down the hill'). And only then , somehow it became too late to scream and run and fight.
I pray for this person to be apprehended very soon. I pray for law enforcement. And I pray for the families of these precious girls. I believe it is vitally important for everyone to be positive and speak positive and think positive in regards to this investigation.
Do I need to add all of this is only my own opinion, theory, and so on? If So, there it is ^^.