Perhaps this verse from Tom Lehrer's "Irish Ballad" might help Ed T grasp the logic of the point Joe and myself were making in regard to condoms:

And when at last the police came by
Sing rickety tickety tin
And when at last the police came by
Her little pranks she did not deny
To do so she would have had to lie
And lying she knew was a sin, a sin
And lying she knew was a sin.