I think you must be right about news events being used as triggers for what the market "intended" to do anyway. Take yesterday's selloff, for example. There must have been people who thought stocks were worth owning before Greenspan spoke, and who decided, on hearing him sing praises to the health of the economy, that this made stocks no longer worth owning.
I find myself wondering about the thought processes of these people.
What exactly was it that they were hoping for, that caused them to be holding stocks before Greenspan spoke, and went away after he spoke? Were they hoping that the economy was doing badly? Or were they hoping that the economy was doing well, but that Greenspan would somehow not notice? <g>
The mind boggles.
And now we have the market's tepid response to MOT's blowout earnings...
(Yeah, I know, this is a "the market is wrong" rant, but I just couldn't help it!)