Crab, my initial post at #12 explains why it may be good idea.
A fenestron type ETR could be stopped in forward flight and yaw control achieved by a simple rudder. Massive increase in component life and reliability.
in the event of engine failure, any yaw in the descent could be controlled by rudder. The ETR would automatically spool up quickly under battery power for the vinegar strokes at the end.
Under normal ops, a conventional variable pitch mechanism would be used.
If made as a 'smart' system, the AW169-type failure could be mitigated by computer controlled reversal of direction of rotation with variable RPM to effect emergency yaw control. All of this is technically feasible today. If the pedals were driven to full deflection and held there, an ETR could be computer controlled to lock the heading. Heading could be managed by autopilot-type hdg bug on the HSI for example. Any excess rate of rotation could trigger a heading lock function.
Food for thought, or just fantasy?
JJ