Today is a perfect example of what I elaborated on in my previous post. Check out the trading action right around 12:00 est. Make yourself a wide 1 minute chart on Stockcharts.com
Whoever did this is a trader dedicated to making pennies on shorting or perhaps increasing his long position by forcing the price down from time to time and rebuying or both.
The third option is less charitable.
News, while this kind of tomfoolery is going on, is wasted IMO.
P.