If there's one thing I'm really s**te at, it's cleaning things!
I use a rubber squeegee thing but the inside of the pinz just seems to make dust appear, which coats the screen and ends up forming swirling patterns when I wipe the screen.
Yeah, I think that idea's out.
Perhaps I need to buy myself a labrador! Put it on one side of the glass, me on the other, job done!
They're never hot enough to make any difference, although given that the pinz is 24 volts it might be hot enough, for a short period ;-)
I think I'll try the washing up liquid idea, coupled with leaving the windows open until I can get appreciable heat from the heater, I'll see how all that lot works together.