I don't think this study has much relevance internationally. For people who have sex regularly foreplay and experimentation is important. For those who have sex infrequently orgasm pattern is different. Foreplay for one thing helps women get 'wet inside' and makes the intercourse last longer and hence gives a better chance of the women having an orgasm. Getting into a dry vagina causes more friction and a quicker ejaculation. 15 minutes is the right amount of time that was spent on foreplay in this study - this is the reason why the intercourse lasted 16 mins. Foreplay also improves bonding between couples- its role in sex, marriage and orgasm will continue to be of importance whatever the study may say.