I HATED when I thought the glass clean, only to see highly annoying streaks later on after the detail was suppossedly complete. So, I was bound and determined to conquor the glass problem, and I did. Here's how:
1: Clean, clay and buff outside of windshield.
2: Use only dedicated zero-pile mf glass towels, and do not wash them w/ other towels.
3: Obtain a zero-pile mf mit/glove to wipe down after you thought you got all the streaks with the other square mf glass towels. Note: You definately should be sweating at this point. If not, keep scrubbing.
4: Obviously, attack from both side of vehicle.
5: Use those glass square scrubb pads/sticks for hard to reach spots.
6: Perform another task, then comeback to the glass and recheck.
*7 (optional) Use verticle wiping motions on the outside, and horizontal motions on the inside. This will indicate what side of the glass the streak is on.
#3 Is, highly IMO, the best step you can add to your streak removal. Buffing glass at awkward and difficult angles is MUCH easier and EFFECTIVE with a mit/glove because they don't bunch and slide around, and skip on the glass when used.
Also, clean your hands thoroughly before handling your glass towels. Also, store them in a ziplock bag.