When i put up up my pole with a large 16 inch brush on it to a window similar to whats going on in this video i felt like a mongey,my brush careered about same as this one does. He lets it go over the edges of the window into contamination territory,IF THIS WAS A DIRTY FIRST CLEAN HE WOULD BE AT IT FOR AGES TO GET A RESULT,this video just reminds me why i wanted to dump all my wfp gear and not bother.
I would hate to perform like that with anyone watching.