Good post! I personally have never gone that long without a guy cumming. Normally they cum in 5-10 min. from the first one, and they get longer and longer as time increases. I have had dates where it was solid oral for an hour and 90 mins. but never without him blowing pretty quick the first time. Even when holding back and switching or slowing down, very few have lasted unless they were on Viagra or drunk lol.
My ex was about 3 min. average during the work day but catch him after 5 drinks, and it was an easy half hour if not more. I won't even bring up "other" factors that will prevent a guy from cumming but I am sure you get my meaning.