Not bad, depending on the nature of the damage.
The idea is to touch up the spots you're after without being very neat - sort of the opposite of what you would normally do - then use the product to remove excess paint once it's had a few hours to dry but before it's fully cured. It works best on small stone chips and scratches that have fairly well-defined sharp margins. You wipe the product across the surface trying to take the touch up paint off while leaving the little that you need behind in the recess of the scratch. Waste of time on wide shallow scratches since you just end up pulling all the paint out of the recess. Once the paint has cured, a little polish & buff to finish and it can look OK. It's potentially a handy trick to have up your sleeve but it's not going to work in all situations.
It might not work for the OP if the touch up job is fully cured since it relies on softening or partially dissolving the blob of paint before it's cured, but it might be worth a try before getting more aggressive.
I used it on rock chips on the hood of my black PT Cruiser that had exposed the light gray primer underneath, so just about anything black would have been an improvement over the rash of white-ish spots.