Thought provoking stuff, I actually did something similar to SSG that I call thought replacement, and it did help improve my grades in school and curb my anxiety.

I used to constantly look at my school work and upcomimg assignments a lot and it ended up giving me so much anxiety that I spent too long on assignments and in some cases never strating them. I changed my approach to only look at my assignments when I had dedicated the time to do them the same day.

I realized that my mood improved when I did this, and now my grades are doing great. You shouldn't worry about something until that moment where you need to but make sure to plan ahead.

I try more and more to only focus on a situation when I can directly can do something about it.

Cheers
@shello