polychords: what's the current state-of-the-art?

[Kieren MacMillan]

Hi all,

What's the current best snippet for rendering polychords? I know the GSoC chord 
stuff is still in air traffic control, but the snippet found at 
<https://lists.gnu.org/archive/html/lilypond-user/2012-02/txtmAr2kxZ1Uy.txt> 
definitely doesn't work, and is likely far from optimal given the decade-plus 
of advances in the codebase.

Thanks!
Kieren.