Double Top: how does this pattern form, what market psychology does it reflect, and how reliable is it in practice? Give a real example only where one is genuinely well known, and say so plainly when it is not.

A double top is two peaks at roughly the same price, separated by a meaningful trough, forming an "M" whose neckline is that trough's low. What it encodes is a price level where sellers are demonstrably willing and buyers demonstrably are not — the first peak establishes the level, the pullback attracts dip-buyers who drive a second attempt, and when that attempt stalls at the same level it proves the supply hasn't been consumed. Some technicians point to the Nasdaq's twin peaks in March and September 2000 as a double top before the deeper 2001-02 phase of the dot-com decline, though the index had already been falling for months by the second peak — exactly the kind of ambiguity that makes retroactive labeling easy and real-time labeling hard. Confirmation requires the close below the trough low; until then, an M shape is just a range. Better double tops have real separation — weeks rather than days between peaks. The caveat: the unconfirmed double top is one of the most over-traded shapes in technical analysis. Vastly more instruments touch the same level twice and then break out than actually reverse, so shorting the second peak on the assumption a double top is forming is betting against the prevailing trend without evidence.