In the Colgan accident, they might have got away with it had they not retracted flap.
This accident could be explained by an early flap retraction, followed by a stall.
Clearly, they would normally accelerate first, but perhaps things happened in the wrong order due to a combination of tiredness, bad weather and business as they started to get on with the inevitable diversion.
I wonder if their decision to go straight back to FL80 contributed?