You are way too concrete in your decisions.
If you got something at $20 , and the rest of us mere mortals have it at $4.80 , don't be such a damn narcissist , and shorten it somewhat.
You won't be backing it , but it will lengthen the Odds of the other runners somewhat , and perhaps reduce what may contain 4 Overlays , down to perhaps just 2.
Bookies don't have animals at short Odds for nothing - if they have them at the wrong Odds , they will get smashed on the other dogs.
Do your form and trust your studies , but don't ignore JOE completely.
I'll do a few races that you do tomorrow , if you play , and I will point out where you messed up.