Animation with MR proxies - doable?

I’ve been using mental ray proxies in Maya 2009 - they’ve been useful to keeping scenes light for animation, then bring in full detail for render.
But what I really want to know, is whether there is a way work with deformation on these guys.

I can get transform animation in Maya by constraining the stand-in objects I’ve linked the .mi filess to: the .mi follows along with their transform changes.
But of course any deformation of the stand-in object doesn’t filter backwards to affect the objects defined in the .mi.

What I’d like to do is either deform the stand-in object and have that filter back to affect the .mi (I know if this is possible), OR bake animation to a mesh and be able to export that sequence as a single .mi.

A bit of a hunt on the internet seems to show people exporting binary proxy sequences, then writing a script to update the file path name every frame to the next file in sequence. But it seems a roundabout way of doing things. I guess I’d just like to know if there’s an alternative I haven’t found before I head down that rabbit hole. Any ideas?

This is along the lines of things I’ve been looking into:
http://forum.mentalimages.com/showthread.php?5510-animated-mr-proxies-in-2009-and-batch-mode