Stepper rotor/shaft re-mounting?

[Rufe0]

Thats not correct, you can hold a BLDC or Synchronservo with 2 different tensions between 2 fases in an angle that is somewhere between that you have with only one of the coils with tension.

Which is exactly what I said...

With steppers you have full torque only at very low speed, and the speed is all but smooth.
With those speeds you cant really work, today with good tools you need a feedrate of more than 60ipm. Rapid feeds of 2500ipm are not seldom, no stepper can move so fast, at least, if you want a
resolution of 0,04thou, like in many industrial machines.

That is the whole point of a many phase stepper, it would be improved in all the areas you mentioned.