[Typo3] Alter rendering of tt_content headings

[Gwilym Evans]

I've been experimenting a little, a reading a lot of the tsref, but just
can't get my head around it all yet. What I'm trying to achieve is
fairly simple in terms of HTML and CSS; div/positioned-based shadowed
headings. But it requires a double-up on the rendering of the heading
text itself.
 
Currently I see the heading text being rendered as (simplified):
	<div><h1>{Heading Text}</h1></div> 
 
I need to somehow alter the TS being included so that headings in this
template are rendered as such:
	<div>{Heading Text}<h1>{Heading Text}</h1></div>

I can see that it'd be possible, I'm able to alter portions of the
included TS libraries to change what's wrapped outside the heading text,
but I can't for the life of me figure out how to output the heading text
twice.

List contributers, as usual your help is always appreciated.

Cheers,
Gwilym