Well the stick dummy offers on the screen to make everyone think...

Well the stick dummy offers on the screen to make everyone think someone is dumping the stock.
Everyone gets a little worried and sells their stock to 37-37.5.
Little known to these people it is the people placing the dummy offers on the stock that are really accumulating (buying) the stock at the levels.
Then suddenly all of the large sell orders come off the screen and everyone buys the stock up because it looks as though there is no resistance.
And then they sell at higher prices.

It happens in all high volume specs