If Buffett's approach to investing has been so successful and widely disseminated, why hasn't it been successfully copied that often?

Probably many reasons, but a few jump out:

1. As a % of Buffett-quoters, there is only a tiny % that acts anything like Buffett

2. Philosophy and process are very important. But so is temperament and judgement, and those aren't 100% learned.

3. Most people can't tolerate the amount of *inactivity* that Buffett's approach requires

4. When most investing professionals can make millions while NOT beating the markets, why work harder using an unusual approach when they can just market a bit more and have more money roll in the door?