Hi Dave, if you have a 3 x 2mtr ext pole take off the end black cap and you can then insert a 12" flat aluminium mop frame which are fitted with Velcro strips, then you can use a damp microfiber waffle cloth to clean the window, then take off the damp cloth and stick on a dry waffle glass cloth to polish off for a perfect streak free finish, this method will give you a better finish than trad or wfp system, the mop frame is shaped to clean right into corners and tight into all edges. if you require any further info just send me an email.
Regards
Tadgh