Don't despair folks, I'm not going to post when I complete all the backdated issues but this was the most challenging so far and from that perspective the most enjoyable to date.
I was going to say that I thought 23d was a great clue even before I read the subsequent posts, sorry aristo.
Main reason for my post is I was surprised but not shocked at the use of the "topless parse" used in the wordplay of 4d!