Have developed an area about the size of the drivers wiper sweep that is very blurry especially when wet. If you wet the windshield & wipe thru the area with a towel it looks like a grayish film but is perfectly clear when dry. The area is very blurry when driving in the rain especially at night. Anyone have a clue about this. Have tried various cleaning methods\agents including light buffing with BonAmi but no change. Almost looks like a layer or coating of windshield has worn off. Is that possible? Thanks for any tips or feedback. dc