How useful is a CFA certificate to your investment return?

I had prepared and taken CFA Exams before, and having scrutinized all that covered in CFA from Level 1 to 3, I would say that CFA materials are useful but will not guarantee you good investment returns!  Those useful topics covered in CFA, you can read from any investment books, don't need to take CFA.  

In summary, CFA is quite useless if you think by just taking CFA, you would become a good investor and make good money from your investments!  In investment, experience and knowledge accumulated over the years is much more important than a piece of paper like CFA certificate! 

If CFA is so useful, anybody who have passed all 3 levels of CFA would be successful investors and become RICH quickly!  They can basically management their own money (just like I do) and don't have to work for other people!