Having two boards running two operating systems with one being basically the slave of the the other got me thinking.

I think it would be rather convenient if the Beaglebone actually booted from the Pi, via TFTP.  One image loaded onto just the Pi could then be used to manage both.

Beyond the initial boot, I'm envisioning it also mounting things from the Pi via NFS.

I went looking and setting up the Beaglebone to do this is possible, and does not look too hard.  There is still the matter of both boards coming up at the same time so the Beaglebone will be looking for the boot image before the Pi OS has begun to start.  I don't know if/how long it will wait, if it will retry the operation, or if it can be configured to perhaps sleep during uBoot to wait for the Pi to start it's TFTP server.

If not, I suppose I could always have the Pi hit the reset button on the Beaglebone as part of its startup.

I'll just have to try it and see.  Probably not now as I'm trying to avoid any more feature creep until 'Make it work first' is a reality.