No worries,
i was first interested in fan jets after watching Peter fogwill using the auto brush, he was the only other guy who seemed to have my phyosophy of using a higher flow, and by using a higher flow actually saving water, at the time I could see pencils and high flow didn't work, the pencil jet hits the glass too hard creating a mushroom effect.
The fan jet produces a flat horizontal stream that forms across the width of the brush head, it's also contained inside the head so no overspay etc.. You can increase flow without spraying everywhere like a pencil, the fans create a curtain of water virtually instantly so rinsing is extremely quick, and with the coverage you can move faster, and move less. You can rinse across the top edge without having to zig zag down the window, so more flow less time on glass water usage is either equal to, or better than slower flow with pencil jets
Darran