I'm a rules girl too! I completely understand paralysis by analysis. In the end, the time doing all the classes, bloodwork and tests proved to be very useful. I really understood what to expect and not much surprised me. There was no way I was going to put myself through major surgery only to break the rules and sabotage my success.
It isn't always easy but being a "rules girl" sets you up for doing the diet correctly because one of the rules is to forgive yourself for days when you may not be perfect. If you slip, ya gotta get right back in the game. Don't wait and make a bad day, two or three or .......
I wish you much success in your journey!