I've made some pretty incredible returns researching and investing, but in retrospect even though I did very well I would have been better off spending that time earning more money rather than investing it. My net worth isn't big enough that an extra percentage gain moves the needle that much.
If you're willing to spend 15-30 minutes per month managing finances, then buy the Bogleheads' Guide to Investing and read it cover to cover.
Once you've done that, head over to the Bogleheads forum [http://www.bogleheads.org] and you can learn as much or as little as you want. Taylor Larimore, one of the authors of the book (and former Band of Brothers WW2 paratrooper), is still active on the forum at the age of 93.
In fact Warren Buffett picked Vanguard's S&P500 fund for his long bet (http://longbets.org/362/)
Agree with the rest of your post. Taylor Larimore is a mensch.
Respectfully, if that were true it would all have been long gone a long time ago :)