If you were allowed to completely delete a post, you could delete all of the responses to it. While unlikely, this could bring up a situation where a disaffected participant deletes a variety of interesting and/or useful postings on his way out the door.

You should be able to delete any replies you've made to postings; click on the edit button and you'll find that along with Save there is a Delete button on the editing page.

I would be happy to remove initial postings for anyone that needs one removed. Just contact me and include a link to the posting.