I have a new Macbook Pro 2017 (No touch bar) that will not boot from an external USB-C SSD drive. I cloned a 2012 Macbook air using Carbon Copy Cloner onto the drive and I have confirmed that the drive will boot from the MB Air. The Air has the newest version of Sierra. (10.12.5)
I have a 2016 Macbook Pro w/Touch bar and it will also boot to that machine.
I have tried to bless the drive in recovery mode (That did not work)
I would like to clone the Air -> new MB Pro 2017
For a long term solution, I would like to be able to make bootable backups of the new machine.
EDIT: I was able to clone the new OS on the new Macbook 2017 and it will boot to that.