Mart,
I think it is fair to say that all air vehicles experience some forms of static and dynamic instability. The helicopter has, perhaps, more instability than most. If we agree that aerodynamics is the major cause of instability, then it makes sense to look, initially, to aerodynamics for the solution.
As previously said, I am not against the implementation of mechanical or electrical means of control. It is just that they are not the first choice. Page 5 of Nick's presentation shows 'control malfunction' as being tied for third at 9%. Assuming that you were to double the complexity of the controls, you would theoretically move 'control malfunction' to second place at 18%.
You mention that " Intermeshing anhedral will reduce [static] stability". This may or may not be true. The 4-degree precone of the rigid rotors is intended to provide speed stability and lateral static stability.
The vertical stabilizer of the Intermeshing configuration is located above the plane of the disks. This has been done so that any sideslip resulting from roll will be 'partially' offset. Any yaw created by sideslip will be in the same direction.
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Slowrotor,
I believe that 'dihedral' has to do with 'static stability', where as 'roll damping' has to do with 'dynamic stability'. Two related but separate activities.
Dave