angersock mentioned sexuality specifically rather than non-sexual relationships. Getting laid doesn't help as much with non-sexual relationships and it doesn't help as much with non-sexual aspect of human beings. For those, I still agree with the advice they should be out interacting with other people instead of reading books, which means interacting with relatives, elders and generally people around you.
Bingo--author mentioned sexuality, which is something that is specifically best left to fieldwork instead of reading Wikipedia and books...and yes, I'm speaking from experience.
Talking to people at parties and raves and orgies and meetups is going to give you much better experience and understanding.
And as for the non-sexual relationship stuff, I'll attempt no general claims at this time.
