I think that if you removed the content of your post, it would be restored in most cases. I have encountered instance where someone wished to recant an opinion or some statement, requested that the post be deleted, and was turned down. The explanation was that our posts are part of the Monastery's history, and it's not good to try to rewrite history.
The only times I've seen actual "deletions" is when someone posts blatantly offensive text, or when it's a duplicate. Even then, you can access the original text if you care to - it's only moved to a less conspicuous place.