he would have finished all 3 by the time i did one with wfp

to be honest,.. i think wfp is quicker over a whole house...( upstairs flick from window to window without ladders)....
but i am certainly quicker with a squeegie downstairs on any window...than with a brush.... think about it, by the time you have washed with a brush and rinsed..... you could have soaped up and squeegied off quicker.
but i am 99% wfp nowadays.