Me and a book is a party. Me and a book and a cup of coffee is an orgy.
Beginner's luck is great for beginners.
Discipline is never an end in itself, only a means to an end.
Business logic and musical logic are utterly incompatible.
There are no mistakes, save one: the failure to learn from a mistake.
If you are playing repertoire material, you're stuck. There's not huge amounts you can do.