No, it hasn't. Their software is just shit, and it lets you access only the last 1k comments/posts on each view of a given collection (e.g. saved comments, posts on a given subreddit sorted by hot, your own comments sorted by new, your own comments sorted by best).
It also doesn't let you touch comments/posts that you cannot access - i.e, if you post on a subreddit, and it goes private, you won't be able to see, edit, or delete any of the comments on that subreddit unless it goes public again. They just won't appear in your history.
Put the two together, and it doesn't matter what kind of delete script you run: if you launch it on your /new page, it'll drop the last 1k comments, minus any comments made in subreddits that might still be private, and stop there. Older content, and content in subreddits that returned to being public after the fact, will still be around.
