I really don't know the circumstances, and I am sorry to see him go.
However, before leaving, he removed almost 2,000 posts, and maybe hundreds of threads. In the process, this removed related "reply" posts by many other members. I don't care about the post volume in particular, but I don't like the fact that our information archive has been depleted in some respects. Removing posts from threads can make them difficult to follow, and removing entire threads robs us of information that should have been preserved. Part of the reason I put so much effort into the software conversion was to ensure that the wealth of information we have assembled here remains intact.
I have changed the forum settings to prevent users from deleting threads they start -- and also from being able to delete their account without my approval. If you have any questions, or ever want to be "deleted" -- just let me know.