If you time it just right, you can use a technique called "cheese grating" to significantly reduce the time and effort required to sand off the micro. Here's how you do it. Apply the dry micro, wait 1-2 hours for the micro to "green", then sand the micro with 36 grit. "Greening" is the less-than-technical term for micro that has begun to cure. You'll know when the micro is greening because it gets rubbery. If you're using WEST, the micro will "green" about 1-2 hours after you apply it. The micro is hard enough to be stable, but soft enough that it sands off soooooooooo easily. It comes off in large quantities, like dragging a block of cheese over a cheese grater. (Hence, the name "cheese grating".) When Nick Ugolini first told me about cheese grating, I was skeptical. But after trying it, all I can say is "Wow!" Instead of waiting a day for full cure, I was sanding within 2 hours of application. What took an hour to sand off takes only a few minutes.
As an example, take a look at the pictures from when I cheese grated my ailerons. It took 10 minutes to big fill the aileron. I waited two hours for the micro to green. Then it took only 5 minutes to cheese grate the micro down to the high spots. The second picture shows the large curls of micro that come off the sanding block. So, 2 hours 15 minutes as opposed to two days to apply the dry micro, letting it cure overnight, then spending the time to sand the micro (hard-cured) off.
Cheese grating also works to sand off the micro in pre-fill areas. The last picture shows an example of cheese grating the prefilled areas on the nose hatch, nose top, canard cover, and forward canopy deck.