My parents, being quite conservative (but not that conservative), had a book on that topic in the house at one point, and I think perhaps I was recommended to read some of it. Thankfully, they haven't followed through with any of that BS, probably in part because it would be too hypocritical given that they dated when they were young, and their parents did so before them (oh, to read some of the comments in my grandpa's diary, mhmm). 😉