it is a lot thinner due to all the impurities taken out
I love these kinds of threads, all of a sudden window-cleaners are scientists/physiscists and molecular geniuses all rolled into one.
My favourite is why windows stay cleaner for longer with WFP, it might do, who knows, but has anyone any HARD evidence as to why, apart from what they dream up when they're bored alone at work and the imagination is in over-drive.