I would say you're still not doing the visualizations correctly. It's not just about doing the mantra and just going for it. It's about being in the moment, visualizing yourself doing it, having the confidence to do the action, and just totally enveloping yourself in the action. Sometimes, you need to do associative visualizations to do your action, and sometimes it needs to be disassociative visualization. It depends on what you're needing that just isn't clicking for you.
I highly recommend that book. If you can get through that book, then your next book would be "Thinking Bodies, Dancing Minds" by Chungliang Al Wong and Jerry Lynch. If you get through that book, then my next recommendation would be "Embracing Tiger, Return to Mountain" by Chungliang Al Wong. That last book is a puzzler, though. You have to be deep in the philosopy in order to understand that last book. Otherwise, it's not worth it to read.
Koffee