First big jump came from the 99 Critical Shots book. Anyone at C level or lower should benefit from it.
Reading AZ has also helped a lot, even though there's lots of squabbling and conflicting info.
A few years ago (like 7?) I made a conscious decision to never bullshit myself at the table
and stop making excuses. I still cry a little like anyone else when I miss and **** up.
But I try to be brutally honest with myself.
This change in attitude has brought up my game steadily.
Examples of this mindset -
- No more tip or cue or chalk excuses. It wasn't the stick.
- Stop twisting and spinning balls just because you're scared of missing.
- Admit when you don't know where to aim to make the ball. (so many people will blame misses on anything EXCEPT this)
- Don't get stuck with lazy wishful thinking, like "I maybe can hold this" or "I'll send the cue ball somewhere and hope it works out".
Lessons have improved my break a lot (thanks Tony) and also helped me fix stroke flaws (thanks Ralph)
and helped with my mental game (thanks Brandon).
That last one is still a problem but I'm working on it.
There were no giant jumps, but there were many
lightbulb moments. I recommend reading that whole thread.