I have a customer (nice hotel) that is requesting me look at about 5K ft of hardwood floor that was refinished last year with a dark stain and Glitsa product. They have a few areas that the glitsa is flaking away where big heavy wood chairs have slid and in front of the check in front desk. They have asked me to quote them for repair and also for best solution (like resand and refinish). they are afraid the flaking will continue and want to do something now while they are closed for the winter for repairs. I have pictures. When i used a 60 grit pad on a grinder it immediately wore through the finish AND through the stain. I was hoping to maybe just remove the finish without having to re-stain. is this basically impossible? what product or process would you recommend to "repair" the bad spots or would you just go for the sand and stain and recoat? FYI there are some areas that have the blister from heavy chair. Some places also seem to be wearing well. This is a VERY high traffic area and i have liked using Bona traffic HD. THANKS for any advice!!!

Definitely sand, stain and recoat(s)

There is no way you can do this the way you intend to. As for touch up on dark stains, unless you're very very good at it, they probably won't come out the way your client expects them to.