Well, I've got a workaround, and I thought I'd just post it, just in case anyone else is interested. I mean, this *is* a rather popular topic thread, with seven replies (six of 'em from me... ;D )

Annnnyway, it's pretty lame, but at least it works: what I do is export the database *twice* with modified templates: one with the results exported to display "Artistname - Title" and the other one exported into a subdirectory of the first one, displaying "Title - Artistname".

Then I manually edit the first index.html to get the alphabetical title list to point to the entries in the subdirectory.

So, instead of
===============
...
<p>Browse by title:<br>
<a href="a.html">A1</a>
<a href="b.html">B1</a>
...
===============

I change the entries to point to the subdir:
===============
...
<p>Browse by title:<br>
<a href="./sub/a1.html">A</a>
<a href="./sub/b1.html">B</a>
...
===============

Well, what can I say?
It's lame, but it works... now on my web site when I click "A" at "Browse By Artist", I get all artists whose name who start with A and their works, and when I click "A" at "Browse By Title" I get all titles starting with A.

The only drawback is that because you export the database twice, your final export directory is twice as large, which can be a pain if you use album picture thumbnails.

This was a Martijn Public Service announcement.

Oh by the way, this in no way invalidates my initial request: if anyone can come up with a single template for this, or suggestions to get this done, I'd be very grateful!