I have had all these issues on my car too..
I have tried all remidies, tricks, products, wipers, services, ... what not
Finally, all it helped is to worsen teh situation and spoil the windshield totally and I am changing it tomorrow with windshield experts.
I have learnt a lesson (rather a lot of them). Many I learnt from my brother who works for Maruti, but not net savvy so isn't seen around here.
Lessons
1. Think twice before you flick your left finger(some cars right) to switch on the wipers. No fault of wipers, but... When stationary wipers are parked horizontally. which serve as a bed for dust and grime. When you switch them on they rub the grime between them and the shield and cause scratches. So Wipers are for use when it rains not for cleaning a dirty windshield.
Now you guys are wondering what the heck the washer is for? it is to give a slight ditergent effect when you use the wipers. Make them work smoothly withou causing the jitter. Don't expect too much out of these simple machines.
2. Windshield is bound to get dirty. How to clean them?
STOP the car. Pull out the wipers. then wash/hose the glass gently without rubbing. If obsolutely necessary use some glass cleaning product for autos. wipe with soft cloth and then with either news paper or better still soft tissue. CLEAN the wipers both the sides of the edge. then put them back.
3. Change the wipers twice in an year. once in the begining of the mansoon, once after the mansoon is over. Bosch wiper are an eldge above the others I have used. They say have soft rubber and hence wipe clean. They do a good job. They do not make noise, leave streaks, smear, etc.. what ever they claim in ads. BUT dealers tell no need to change for 2 years. DONOT believe them change in 6 months. They hardly cost 400 bucks. worth the money.
Please change them even if you do not use them at all. Rubber gets hardened and become useless.
4. NEVER try any sort of abresive on glass. However fine texture. It just spoils the glass. forever. I tried and am paying for it today.
NEVER use acetone. I am the idiot who used it on the camera lense and scrapped an expensive camera. It will cause blurr effect on the surface as in sanded glass.
5. If the damage has happened change teh glass immediately. I know its expensive. but SAFE. It cause discomfort with oncoming traffic head lights due to glare. But the problem is BIGGER than discomfort. You will not be able to see teh darker part of the road, where in India pedestrians lurk.
6. If you are seeing glare, as some one mentioned on the thread. It will not be just smear. It must be micro scratches. Nothing can be done about it. replace glass.
7. Wind shield experts do not fix any windshield related problems. They are experts in replacements. and fixing chipping due to minor accidents. They do a better job than most auth dealers in Bangalore.
Prevention is the ONLY cure!
Take care.