If you can trad that piece of glass to rule out its not just poor glass.
When I switched it opened my eyes to how much crap glass there is,I think we notice it a lot more than customer we have a good eye,doing this for a living.
Spots can be ingrained in glass.
I was going to say the exact same.
When I switched over I checked some windows and thought they were spotted all over when I looked at them a certain way (with the sun directly behind you, or street light)
I was so bothered about it that I did them again trad and realised it was little spots all over the glass that could not be cleaned off. It was erosion or a deposit of some sort.
I had been cleaning them for years and never even noticed.
When we were trad we didn't take a blind bit of notice, just soap it up, blade it off. Window dry, then moved on. Now I think we can be far too critical with ourselves and paranoid.
Check to see if those marks come off with a cloth tom. If they do, then it's a water/technique problem. If they can't be shifted then you know they have been there a while.