Don’t worry about the final rinse, that’s all it is a final rinse!
Do a test; clean your own ground floor window ‘pane’ one with and one without a final rinse, then compare the results. Work on ‘cleaning’ the glass, rather than relying on the rinse. Half the time I don’t bother with the rinse with my regular customers, I already know the results are going to fine and the windows I do rinse regular are no more than 1 – 2 seconds at most. It’s only the occasional jobs (2-3 jobs a week) that require a thorough rinse then usually another quick clean because of more dirt than usual.
How often do you go over the glass?
If I let's say scrub the glass once toroughly, and once rinse brush on quickly, with my work, which consists of 4, 6 and 8 weekly customers, this only gives me about a 60% succes rate or so, only the really clean 4 weekly ones I can get away with it. I've done a lot of inside/out cleans, and it's really hit and miss on most properties. Not the level of quality I am satisfied with.