I had been meaning to read this article at Catholic Exchange all day and I finally got around to it. This article really makes a clever little analogy to drive a very difficult point home. I enjoyed it and thought it was an easy, good read. It is a meaningful, memorable way to present the idea of NFP and contraception to young engaged couples - anyone, really.
But I still don't think I'll be giving up Diet Coke anytime soon. :))
And on a side note: He is right! Everything here in Texas is a "coke."