I was on a forex conference ca 2 years ago, there was one man presenting his great results, do not remember now well maybe 10 000% in a month or 1 000% in a month, not so much important actually.
After his speach people asked him which trading books can he recommend...
I remember he answered that he does not read anymore books about systems/techniques/technical analysis, he just reads books about psychology
Could not understand it well at that time, but now can only agree
It took me a while to understand what counts most in trading :-)