> Buffet's results are unlikely (though likely the result of many different strategies, some successful, others not...), but in a market with so many investors, it is perhaps not so surprising that one so successful arose?

Quite correct, in fact, in an equities trading community the size of the present one, successes like Buffet's can and do result from chance. This is not to claim that any particular one does result from chance, only that this possibility is the first one that a scientist or statistician would need to consider.