It's a loosing battle, for me to explain this subject, because several people are struggling with different area's. One camp doesn't understand that no matter what, time falls out of general relativity as a symmetry of the theory, it is not a true time evolution. The other camp is finding it hard to understand what an observable is in physics, or why time isn't classed as one, why looking at a clock isn't an observable, ect. The only person I think can give a clearer picture of this is the man who has actually worked on the problem of time in GR for well over 50 years. (I believe in this video, Julian explains all the important things and I believe he makes a point of mentioning time isn't an observable. If it isn't this video, I will find it) https://www.youtube.com/watch?v=gOdk-u9wTkM Now, listen to him closely. Please.