MP:
With accident #3 caused by poor maintenance procedures and/or fitting of the new actuators.
Maybe, just maybe, you're jumping slightly ahead of the Danish NTSB here. They haven't finished their investigation yet regarding who caused what, and you shouldn't speculate, if you consider yourself an aviation professional.
SAS should have waited on the outcome of the 3rd accident before making their decision on the Q-400 which in hindsight looks like a mistake. Flybe's response was certainly well thought out and proper.
SAS didn't make their decision based on the safety of Q400. They haven't questioned the safety. But they care about the brand "SAS" in the eyes of the costumers, and after 7 years of more or less lousy technical reliability, followed by 3 accidents in app. 1 month, they have come to the end of the road. Where do you suggest they draw the line, if not here?
Flybe, mind you, have NOT had 7 years of lousiness followed by 3 accidents, so no wonder, their costumers have a different view on Q400 than SAS'.
It's not THAT hard to put yourself in SAS' shoes, if you try just a little bit.