‘Write post’ – split ‘Post’ textarea into 2 columns?

Kaf has written some nice code to split a post into two columns:

<?php $content = split(“<!–nextcolumn–>”, $post->post_content); ?>

http://wordpress.org/support/topic/68137?replies=9

To use this, I add <!–nextcolumn–> into the post where I want the next column to start.

Would it be possible to create a customised ‘Write Post’ page, that actually displayed these columns in 2 distinct text areas? (For the benefit of a client.)

Pages with one column would revert to the default editing layout of course.

I’m more of a hack&paster than a coder but would be interested to hear your thoughts on tackling the above 🙂