Can a Mage be Both Communion Slave *and* Master?

[Yrkoon]

So if you make the mages that come last in the unit ID order communion masters, and the unit with smaller ID numbers slaves, all the slaves can cast spells, plus they benefit of the spells cast by the master(s) (say earth power or power of the spheres), plus the masters have they paths boosted by the slaves (on top of earth power and power of the spheres in this case) ?!? Am I getting this right ?