Elevator problem?
This has probably been mentioned, but I don't have the time to check the whole thread:
According to the FDR traces in #173, the right elevator appears to be acting strangely. There are five or six areas on the trace where it is deflecting when the left elevator isn't and vice versa.
I wonder if there was a flight control problem? I have never flown the CRJ and I don't know its technical arrangement - is each elevator controlled by a different computer? Or perhaps they had a hydraulic system failure which only affected one side?