Sorry, I won't have a solution for you either, but thought I'd chime in on the subject.
This kind of problem is one of the things that scares me about dynamic blocks. When we create a new drawing, let's say it's an electrical schematic, we insert all of these blocks wherever they're needed. Let's use a switch for example. If we insert a switch as a dynamic block and change its state to Normally Closed, we finish the drawing, print it out and all is well. A year down the road, changes are needed to that drawing, so we open it up but something screwy has happened with the block for whatever reason and the next guy goes to insert it into the drawing again, changing the state of all of the existing occurances of that block back to whatever the default is. The CAD operator is totally oblivious to this change, but finishes his markups, prints the drawing and distributes it. Two months after that, at 3:00 am, there's an emergency and the maintenance crew needs that drawing to troubleshoot, but thanks to a screwup with a wonky dynamic block, they are unable to find the problem in a timely fashion.
Ok, maybe that's a farfetched scenario, but it is one thing I have thought about regarding dynamic blocks. I don't know whether that scenario is even possible, but ...
Sorry Dan... I hope someone's able to help you out!