each rally is just an bubble
at some level, the bubble "po",
you will find yourself so dumb to buy so high
I know one of my friend who bought YHOO at $250, he tried to be smart in .com bubble, he still had his shares, each time when he mentioened his $250 yhoo purchase, he feel he is a dumb
he said he want to holdit forever, remind him always: the risk is so great when he buys HIGH/TOP
when look around, everyone is making money, then watch out, the down side is there, the odd to buy exact top greatly increased
donot be a sucker! be a cold minded trader/investor, that is the only wise thing to do!