There is not just a discussion about it, it is already implemented! (Admittingly one cannot really tell from skimming http://wiki.splitbrain.org/wiki:useheading
. It is quite hidden, because AFAIK that feature originated from that discussion.)
To use that feature just change $conf['useheading'] = 0; in conf/dokuwiki.php (or conf/local.php) to $conf['useheading'] = 1;.