Famed investor Peter Lynch took the Magellan Fund from $18 million in 1977 (when he took charge) to $18 billion when he resigned in 1990, posting a 29% average annual return in the process. The way Lynch achieved those returns is discussed in his book, Beating The Street.
Across a number of industries, Lynch discusses the key success factors that drive a company and its stock's performance. He shares the attributes he looks for in banks, retailers, restaurants and a number of other industries, suggesting he has a wide circle of competence.
While there are value elements to Lynch's approach (though he doesn't bring up Phil Fisher, Lynch definitely uses scuttlebutt to his advantage, and is clearly a fan of low P/B and low P/E), I have to say I was somewhat surprised to learn how Lynch analyzed his stocks under consideration. There was little discussion in the book about competitive advantages, but there was a lot of talk about industry trends. Lynch appeared to have his finger on the pulses of various industries, as he spent a lot of time talking to managers and gleaning trends.
The other surprising element was the sheer number of stocks in Lynch's portfolio. He achieved his 29% returns not by concentrating in a few stocks that rose in value, but by investing in hundreds of companies at once(!), all of which he followed himself. It's probably worth noting that the market was up over 15%/year in the 13 years Lynch put up his remarkable returns; though we won't get the chance, it would have been nice to be able to observe Lynch over a longer time period.
You can get the book here.