If you have a 1A motor, you set the drive to 1A and if you measure the current, your ammeter will read 1A just as advertised.
The drive is a 10-microstep drive, so the currents will look like this for each of the 10 microsteps:
microstep 0, 0.078A, 0.997A
microstep 1, 0.233A, 0.972A
microstep 2, 0.383A, 0.924A
microstep 3, 0.522A, 0.852A
microstep 4, 0.649A, 0.760A
microstep 5, 0.760A, 0.649A
microstep 6, 0.852A, 0.522A
microstep 7, 0.924A, 0.383A
microstep 8, 0.972A, 0.233A
microstep 9, 0.997A, 0.078A
The current is a sine that has a peak value of 1A and an RMS value of 0.707A. So, why not jack-up the RMS current from 0.707A to 1A? You can do that by multiplying the motor's rated current by 1.41 and set the drive to 1.41A. Now the RMS current equals 1A; sounds good doesn't it? When one winding is near zero Amps the other winding is at 1.41A so everything should be even.
Well, it's not good unless you like a rough running motor. Step motor windings don't share a common magnetic flux path; you can prove that by trying to use the motor as a transformer.
You are putting in 141% of the motor's rated current, the iron will saturate and distort the motor's motion at low speeds. In other words the motor will vibrate at certain low speeds. You use a microstepping drive to eliminate vibration so this is going in the wrong direction.:-)
Finally, consider this:
You have a 100 oz-in holding torque motor. You drive it with a full-step drive and you get 100 in-oz of holding torque. The moment it begins to move, you get 65 in-oz of low-speed torque. Where did the missing 35 in-oz go? They are invested in vigorously vibrating your motor.
You don't like the teeth-rattling vibration of a full-step drive so you haul out a half-step drive and there is less vibration. But take a look at the half-step sequence; it's both windings 'on', one winding 'on', and so on. Alternating strong steps (100 in-oz), and weak steps (71 in-oz). If you overload the motor, it won't stall on the strong step. For all practical purposes you have a 71 in-oz motor now.
Take the same motor but use a microstep drive. You get 71 in-oz of holding torque. The moment the motor begins to move, you still get 71 in-oz of torque. Why? The motor isn't vibrating so no torque gets squandered.
Compare the drives: 65 in-oz for a full-step drive with terrific vibration, 71 in-oz for a half-step drive with less vibration and 71 in-oz for a microstep drive with almost no vibration at all.
Now jack-up the microstep drive current 1.41 times to get your 100 in-oz back. The moment the motor moves you will be investing some of that gained torque into vibrating the motor again.