Question: Is there any valid reason why the stock bootloader must be replaced for the LE11+ image?
I'm only asking this because it seems that the box image can run from an SD card under the factory bootloader without any problems, so I see this as an unnecessarily dangerous thing.
This is exactly why I don't dare to use emmctool, because at the moment it doesn't seem like any kind of "disaster recovery" would work for WP2 and the Hub. One thing is certain, that the number of problematic cases is much more than zero. Knowing this, I consider it a bit risky to release not sufficiently tested images that overwrite the factory bootloader.