Hi Jennifer,
Personally, I see nothing wrong with their teaching that sex is another gift from God -- for all married couples. On the other hand, I do believe the "roof-top escapade" is a bit over the line. Focus On The Family has always discussed the sexual relationship within marriage and shone a positive light upon it. So, that part is right on. But, the theatrics do seem to be an over kill -- and I have to agree with a couple of comments left by folks, wondering if this is a publicity stunt to increase sales of their book.
On the other hand, I do believe, without knowing them personally, that their ultimate motive is good. I have known pastors who use gimmicks to emphasize sermon points -- as this pastor did in an earlier sermon when he had two luxury cars driven onto the pulpit stage -- to emphasize that we, as saved believers made in the image of God -- are the human equivalent of the Rolls Royce. Good example, even though a bit overboard. My senior pastor used to use good examples to emphasize points (not to this extreme) and they were very effective.
So, I suppose I will take a "wait and see" attitude on this story.
God bless, have a wonderful, blessed day,
Bill