I’ve added a patch to the tracker. It’s the superstructure for a new modifier, in case some kind soul with a bug up their butt for the functionality previously described wants to show up, write only the hardcore code (the bind and deform) and take all the glory. Let me just say that this modifier will be used constantly, by everyone. Maybe even the Pope. So you’ll have that going for you.
But really, who am I kidding? I’m going to end up fighting with this all weekend and into next week when I should be writing my book.
Tracker link: Similar Surface modifier patch