No one said he should "sell", whatever that would mean. I just was responding to the idea that he continued on, doing the same thing, even when the trend had turned. That obviously didn't work as he lost 70% of his profits. I just was pointing out that sometimes people may recognize that it's time to take a profit and try a new tact. And as far as Mark Cuban and Prokhorov go, maybe they were just lucky. I've heard that Mark Cuban shorted the market heavily on the steep sell off from the Dot-com bubble. But that may be just part of the myth that surrounds him.
In my years of trading, one of the most prominent things I see over and over is that when the market turns it takes most traders quite a while to change their strategies. After the market has sold off and starts to rally many people are still trying to short the rallies but this obviously doesn't work then. And when the market has peaked out most of us are still trying to buy the dips which doesn't work either.
I'm not criticizing Dan Zanger. He had the balls to put it on the line originally and did extremely well. But one does need to be able to change ones trading tactics and strategies when the market conditions change. That's what makes someone a really successful trader, like a Paul Tudor Jones for instance, who made some of his biggest profits when the market turned.
http://en.wikipedia.org/wiki/Paul_Tudor_Jones
BTW is Wittgenstein your real name? I used to be a philosophy major in college.
"Whereof one cannot speak, thereof one must be silent."
Ludwig Wittgenstein