It is the nature of rallys to sneak up on people. How do the market makers do that knowing that there are a lot of smart traders out there watching the action? Just get them leaning one way by noting what indicators that the traders watch and manipulating things to go that way for a while and then go the other way at the last minute.
The price is the primariy indicator, there is not much that the manipulators can to to that without tipping their hand.
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