_Bandit_, Vicki Hearne, p.205, has heard of this:

``For example, I was once involved in a panel discussion at
which the idea was voiced and elaborated that riding horses was
a good way for girls to prepare for marriage because it gave
them practice controlling something powerful and dangerous
between their legs.  I thought, and at enormous risk of self-
exposure said, that controlling something powerful and dangerous
between my legs didn't characterize either marriage or
horsemanship as I had experienced them.  It is true that some
activities that fall under the heading ``sex'' can be dangerous,
but before AIDS it was the thing the man sometimes had in his
hand, and not the thing between his legs, that was worrisome.
And there are some differences between husbands and horses
that I thought worthy of consideration, including the fact that
in the case of husbands direct mutual genital contact is to the point,
whereas it interferes with horsemanship.  I don't doubt that it
is possible, only that it is horsemanship.

``The persons propounding the P&D Between Your Legs theory were both
male shrinks, and Lord knows what they made of me, given their
experience of horses and other things between their legs.

``I am sorry to speak so crudely.  There are many men of subtle
and strong hearts and intellects who quite easily distinguish
between horses and penises''

  Vicki Hearne, _Bandit_, p.205