Common sense is not that common, as we all know. Also, the stock message boards, as much fun as they are, can go along way to separating a reasonable person from their common sense and good instincts.
That's now why I now make it a point to spend a fair amount of time from the internet when I'm not actively trading. It can be very seductive, and that itself should be a warning sign.
Momo has said that take a good trader away from the message boards, and leave them alone with charts and Level 2s, and most people will make the right trading decisions. It's often the 'chatter' on the boards that cause people to override their good sense and instincts, and make decisions that in hindsite were foolish.
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