If it's depositing a layer, that will lessen the extent of fissures and round them out. That's a great thing to be convinced with polishing. This adds to the valleys and polishing removes from the peaks, making an overall much flatter surface.

Where I think this would really shine is with receding gums. It'll be able to slowly add protecting to a part of the teeth that has absolutely no protection. That will help "clog" the pores and reduce sensitivity as well as likeliness of a cavity.