This humor is really quite mild. I have to think that you just don't get this type of humor. There is nothing abusive, arrogant or distasteful in the post.
So if there really is such a thing as a sarcastic Christian, what is so bad about this post? Is it the length of the sarcasm? Should he have stopped at one paragraph? Should he have just take a small minor shot in jest? With all sarcasm, there is always someone who can take offense. The key, however, is that it is up to the person to take offense. Do you believe his intention was to offend? No, he was just trying to be funny. So why take offense?
Perhaps you think we should play it safe. Our mission is so important that we can't afford to place anyone in a position that they might take offense. No, we can't walk around on eggshells. And it's the funny stuff like this that shows people that we're real people, not just happy smiling easily entreated Mormon clones.