Arriving flying & rotor/fenestron speeds?
Re Double Bogey: the helicopter arrived on the pub roof without any rotor speed, according to the AAIB. I don't think that necessarily implies that it arrived 20 feet above the pub roof without any rotor speed. The violence of the impact will surely eventually be measured securely from analyzing the deformation to the wreckage, the radar trace and any CCTV/sound recordings that might surface.
Re 212man: My understanding is that the speeds of the rotor and fenestron are locked together, but that they have fully independent pitch controls and approximately orthogonal incident airflow. As such, I would expect that one, neither or both could be stalled (or thrusting) provided that they are turning at a reasonable speed. I'm not sure that anything about the mechanical state of the wreckage is currently valuable apart from the statement that everything appears to have been found intact and moveable.