Joe,
While I can see that what you said in a prior post could cause issues with the provisioning process, the only one that seemed as though it could cause the unattend truncation error was joining the base image to the domain prior to capture. I have always kept my bases off the domain prior to capture as I've read that this is best practice (can't recall where I got that impression, but I haven't seen anything to dissuade that). I don't doubt that there could be something in my process that causes this, but I fought with this long and hard and really seems to be a MS process within Sysprep. I guess what needs to be figured out is how to get visibility into whatever this process is to find the variables that effect it. I was hoping someone would get something from MS on this, but alas.
No offense taken, I realize you are trying to figure this out also and are pushing to get as much information as you can. I respect that desire. Whether this is a bandaid or not, I have no idea. Our process may end up oozing blood out the corner of the bandaid down the road, but for now, it is getting us to the desired result without those annoying failures.
Thanks for your input.