Microstepping and stepper torque at high RPM?

Greetings,

As I understand it, stepper motor torque drops as the RPM increases. At
a given RPM is there any difference in torque for different
microstepping values?

If a given stepper could generate X oz-in at 2000 RPM in quarter
stepping mode, should I expect the same, more or less than X oz-in at
2000 RPM in eight stepping mode?

thanks
cs