I have been thinking about this for a while, with our jets mounted in the usual way the water has to fight it's way through a mass of bristles to get to the glass when we are scrubbing.
I am experimenting with flexible jets, the actual jets are made from brass wood screws and are about 6mm in length, these are inserted into Algarde silicon hose.
the actual jets are level with the end of the bristles, in fact the bristles help to keep them in place.
This way the water is right where we need it.
The jets are pushed down about 2 mm inside the hose, so no danger of scratching glass, the silicon is soft so no damage there either.
You need to drill 5mm holes in the brush, the Algarde is 6mm in diameter so you have to screw it through the hole but it will go.
Your thoughts are welcome, Dai