I'd love to see this technology re-visited and perhaps revised.
The one drawback in using this technology is that it uses the neck pickup as the driver.
I wonder if there is a way of triggering the vibrations in a different way, which this gentleman has just barely touched, by utilizing the bridge saddles, but also adding perhaps a driver that mounts in the neck or fingerboard itself, such as Epiphones NanoMag that they use in place of piezo's for thier acoustic sounds.
By having the sustain circuit tied this way, it would allow the neck pickup to be used, or actually any or all pickups, simultaneously or individually.
Take into consideration that the original Sustainiac circuit mounted to the headstock and wasn't reliant upon the magnetic interaction with the pickups to generate the sustain.
I know there are plenty of folks out there who would live to use this technology if it weren't for the fact that they can't use it on a neck pickup, or on #2 or #4 on a 5 way setup.