No I don't go through the lathe bed! (I've emailed David Blaine asking if this is possible though)

If you look at the type of lathe I've got...

http://www.axminster.co.uk/product-A...the-564883.htm

that control box on the front adjacent to the chuck, inhibits the use of the chuck key in any position except insertion at the top. If I had a long nose key I could adjust the chuck a lot more freely/speedily (eg just rotate the bottom jaw up a bit, bosh in the key adjust - back down...then adjust the top up etc)