THE Bipolar Stepper Driver. Have you seen it?

[John S]

Every time you microstep you loose torque.
So by the time you drop down to 1/16th and need to overcome stiction it will miss steps unit it has enough to make a sudden move so basically anything over 8 is a waste of time.

Also remember systems can't remember microsteps so a shut down and start up will go to the nearest full step regardless of where it was.