I use a sill brush with fans, also clean the top of frames/vents....dont get problems....
if your going to rinse less, really you should have your flow a little higher, or at least rinse on the glass. For me the rinse is more important than scrubbing the window 12,000 times, so when people have said they can spend less time on a window, i took that to mean they scrub it less, but still give it a rinse?
As lee Gls had said, my bottom few rows of the brush dont touch the glass only the sill, so i dont get a problem with the jets pushing the water up as they're at a decent angle...
Also found on the downstairs windows that sometimes rinsing from the side (so the jets are spraying vertically) is better than rinsing infront of the window (jets spraying horizontally)
They were a ballache to get used to though, but now i wouldnt be without them (i use pencils on 45footer for accuracy though)