Its not negativity kempy, its realism!!
Show 2 dried windows, one cleaned by vision and one by pure water alone! Then explain what difference you see, if any!!
Glides easier,,,,we all use slippery stuff called water, which makes gliding work.
Water bonds with additives, so yes will help with maybe a quicker rinse n uniformed drying time.
Sparkle,,, yes just a wet window looks sparkly, but then vision is an additive
Bubbles,,,,,,no benefit, apart from the rest of sales talk as above, than to convince gullible customers into thinking that its doing some miracle on their windows, that pure water cant. To sign the deal thats its a more sophisticated clean, we will convince you by that sweet pleasable clean odour, to sweaten the deal!
Im amazed at how many people can be gullible. Lol how many went out n bought daz for our clothes. It got them, whiter than white.......but then a new box of daz came out, showing how the old was a little rubbish actually and the new version is whiter than white!!!!! Lol its the same gullibility but for men, window cleaners