I agree that cas knows dean’s deepest feelings and motivations and stuff because he can see/has touched his soul, but i feel like there’s probably an aspect of dean that cas doesn’t understand that sam does, cause its just like. unimportant things that dean has very strong opinions on (pineapple on pizza, etc etc), or stupid inside jokes. And sam gets it, cause siblings are just like that, yknow?
Like one day cas overhears sam call dean “jerk” out of nowhere and dean immediately fires back “bitch” and cas is just like. “But you were fine five seconds ago? And now you’re fighting? Why are you being so mean to each other??”
Idk man i just don’t like it when cas knows like everything about dean. Should be more like yeah you can recount his biggest regrets and his motivations and his deepest secrets, but what’s his favorite soda? And then we get these little gems of dean (or sam! Sams here too) explaining random human behaviors to cas
