I have never found any water in either of my separators, the one I added or the factory one.
I have had bad fuel one time, truck started sputtering about 20 miles down the road from a fuel stop I had never used before(Haugan,MT. ). It continued acting up until I got home. I drained my separators, no water, I dumped some Power Service 911, and Arctic Express fuel conditioner in and filled back up at Albertsons, where I purchase 75% of my fuel. After a trip to Post Falls, and back to Spokane, about 40 miles from my house, and all was back to normal.
I am sure folks do get water in their fuel, unfortunately my separators(BF1212/factory filter)must have passed it through???