@umfriend - Thanks! I think that solution will work for my current situation as well. Only downside I see is that it always requires physical drives that can be set up in equal pool sizes, otherwise losing duplication space.
I wanted to check to see if this was ever resolved. I will be encountering this configuration (two partitions on the same physical drive) and I want to make sure that DrivePool will not place duplicate files on the same physical drive.