Well guys, I may not be expert at much around here, but I can answer this question.
I have spent 26 years in the glass industry.
Essentially, if you can feel it with your finger nail or credit card, you can not polish it out with out serious distortion to the glass.
If it is annoying now, when there is distortion will it be even more annoying?
If not, get out your rubbing compound, and power buffer, and go to town. Just like with your paint, you will want to work to a finner and finer polish until it ( the scratch) is gone.
Just remember that the area you polish will be somewhat distorted.
Hope it helps.