I hadn't seen this when it was first published but it's really awesome. I thought "More Than You Know" was a great book and highly recommend it.
The idea that there are stocks the big boys aren't going to waste their time on (yet!) is key to why I believe that retail investors can do well. When I look at Intel or Wal-Mart, I always think about the fact that Fidelity, Goldman, Legg Mason, and many many many others are looking at the same things (and more) that I am. How much excess return is really likely in that situation? On the other hand, smaller stocks, with many fewer eyes on them and wild price fluctuations more prevalent, seem to be a much better place to find mispricing.
Mauboussin's focus on process rather than outcome is also interesting. There are a few times I fell into the trap in the past where I would pick a stock for the wrong reasons but get a good outcome. The result was typically that I would continue the bad process and end up with a number of poor investments on the heels of the good one. Even though a well thought out, refined process may not lead to good outcomes 10 times out of 10, it's what's going to give you long term success in the markets.