Unfortunately spruce I am talking about the karcher, tbh it does work really well!
These sort of high access jobs never seem to run well and straightforward, I think mainly because they don't get cleaned very often, I like your idea of squeeging across the glass I've always gone top to bottom.
Be careful going bigger with a channel, getting them to sit flat is very hard.
So far our best and consistent effort has been to mop, squeegee then buff with lightly damp microfibre.
Next time I'm going to mop then vac with karcher to see if I can get consistant results at 30 ft up
Darran