No prob James,
I thought I saw another response from you, but I can't find it now to respond to it.
Anyway, I ended up going with the first solution I mention in this post: viewtopic.php?f=7&t=3001&p=14588#p14588
We are using mesh deformation as well, but for those attachments, we either ignore them or use a bounding mesh to approximate the position of the mesh regardless of how distorted it gets.
It's working, but it could use a lot of refinement. Enemies and characters can interact with the environment well, but sometimes their animations cause them to be really unstable as their revolute joints try to keep up. I'm happy with this for now, but I wonder if there's a better solution out there...