Clay will get any bonded on contaminants out of it. But as for chips you can't do anything.
Cleaning glass shouldn't be a quick thing. I use a couple of glass clothes, one for the cleaning which gets rather wet, and one for drying to prevent any streaks. With a windscreen do a bit at a time so you get it all properly. But the inside of the windscreen is my most hated of all cleaning jobs on a car
Quote Clarkson, Top Gear, 17th July: "I'm not having a stroke... just driving a Nissan!"
Quote Ry, Mallory Park, 3rd Dec: "Ahhhh crap... Just a bit too over eager really!"
"I used to be an adventurer like you, but then I took an arrow in the knee"