Man it took a while to find this post as I'm still new to this site but holy shit was it worth it!
I assumed that each route was it's own outcome but also giving hints towards what really happened with this group of friends during the week.
Now that I've read through route 65 I agree that Chase's personality does change drastically during each route. And this explains the inconsistencies I kept running in to.
My "focus" had been Flynn almost as a control for the bizarre situations happening (until you get to the end of course).
I tried to collect what we knew as "the facts" and piece together the picture by finding out Chases "real" personality and what choices he would've made if he wasn't possessed. This just broke my heart more for leo when I read "The party" from what it seems to imply.
I know this probably sounds ridiculous now, but it was fun thinking I was getting it. :P
I'll be reading through this story again with this information in mind and will love to check out Tsr and Arches when those are completed.
Thanks for the amazing theory!