In a survey carried out on the HaPenis Project website slightly less than 4% of Men described themselves as “Exclusively Heterosexual” The survey used the 7 categories from Kinsey Heterosexual–Homosexual Rating Scale, is used in research to describe a person’s sexual orientation based on one’s experience or response at a given time. The scale typically ranges from 0, meaning exclusively straight, to a 6, meaning exclusively gay. The reports were first published in Sexual Behavior in the Human Male (1948) by Alfred Kinsey.

I agree. I believe many – if not most men are sexually fluid. Depending on time, place and circumstances (who he’s with) a man can act on a variety of sexual activities. That said, social stigma can prevent them from admitting to straying off the exclusivity heterosexual path… even in a private poll.
great statistic I’ve suspected all along