I found, for me, doing it the opposite way worked better. Dial down the VVR controls to a desired volume level and then tweak it from there.
You can't completely reproduce the exact tone you had with full power while keeping the amp settings set the same way once you lower the voltage. Tone may have to increase/decrease a little. The breakup or lack of, at let's say 5 may need to be adjusted closer to 4 or 6 and the interaction of the two volume controls might change slightly to. Sometimes no adjustments are needed.
You can't completely reproduce the exact tone you had with full power while keeping the amp settings set the same way once you lower the voltage. Tone may have to increase/decrease a little. The breakup or lack of, at let's say 5 may need to be adjusted closer to 4 or 6 and the interaction of the two volume controls might change slightly to. Sometimes no adjustments are needed.