Thank you for the video, very informative and I actually enjoy that geeky side of stuff!
Personally, I use about 30m of Gardiners 5mm reinforced pole hose on my main reel (the other 60m is microbore), because I had tennis elbow (rather painful) and the 30m is really easy to pull and move around.
So technically the smaller diameter of the 30m pole hose does restrict the volume of water.
However, I have just fitted a new sureflow pump which re-calibrated to 35. (I know, this sounds very low) but this gives me about 7-8 feet jet of water using 2mm jets and a Gardiners extreme sill brush, which I think is a fairly decent flow.
This is just my opinion, but I like a good amount of water under the brush when I'm scrubbing; so I'm sort of agitating and 'partly' rinsing at the same time. I find I can achieve this 'good amount of water', whether it's pencil jets, fan jets (which I sometimes use) or Xline rinse bar (which I sometimes use).
So, for me, providing I have a good amount of water under the brush, for scrubbing, I don't mind which method I use. Having said that, I do prefer the standard 2mm jets. For large areas of glass the longer bristles and rinse bar of the Xline brush is brilliant.
So the final rinse is 'a bit of a gesture', ok I use that term rather badly, but hopefully most of my work is done with the scrubbing and same time rinse. For me the final rinse is a rather quick affair.
And, in this weather, it's easy to check your work.
Thanks again for the video.