the reality is theres no time for that on a busy round , as long as i clean the frames well with a wet rag with CIF on it the first clean, from then on a 2 second rubover with the scrim is all thats needed to maintain the gloss
also id say be careful of using anything thats not a regular cleaning fluid, as it might come back n bite you in the bum one day, if a window frame fades theyd have grounds to sue you . its a very claim happy world out there now