Hi handlewanker,
I think the advantage of the wormgear is also to drive a high torque with
précision.
However, in some case you may need high speed rotation then precise move or position. This is supposed to be torque motors specificity, how ever on the same system the system I talk in my latest post it's possible to make speed variation with a worm gear (actually it's dynamic backlash variation to allow important shaft rotation change.
you can visite
http://www.allytech.eu/index_fichiers/OTTMATIC.htm