Intrafamilia sex also provided a sense of security for the younger members of the family, too. Teenage boys are, for the most part, clumsy and inept when it comes to giving a good sexual performance. A young boy often requires the expertise of an older woman, and a young girl, especially a virgin, requires the calm but knowledgeable behavior of an older man.

In sixty-eight percent of the cases studied by Dr. Dormann, he found a history of impotence with partners outside of the family unit. Sexual vigor returned only when the older male had sex with a close relation. This reaction is entirely consistent with known mental and physical responses when the individual is confronted with a situation where his security is threatened. The Encyclopedia concurs:

"… the principal reaction (to fear) is the arousal of the sympathetic nervous system."

When a person finds himself in a threatening situation, large quantities of adrenalin are secreted, quickening the heartbeat, sending blood to the brain and muscles, and in general mobilizing the organism for fight, or flight…

When an inordinate amount of adrenalin is pumped into the blood stream and the individual is mobilized for fight or flight, his sexual responses are almost non-existent. Naturally, impotency occurs. A man gripped with the impulse to flee, or defend himself from a threatening situation is in no condition or mood to perform sexual activities. Many men and women during this turbulent era of the 1970s do find themselves in a condition of mental and physical inadequacy when confronted by a situation outside of the family unit.

As the Encyclopedia goes on to say, "… there are situations, especially in panic, where the body becomes over-mobilized and behavior becomes disorganized. Moreover, if the state of arousal continues for a long period of time, the continual drain may result in psychosomatic disorders…"