... very interesting.
I haven't had access to that last Dragon book, for quite a while.
iirc - Wyrm of War doesn't have to use all of it's Sorc stuff, to add in the ToB stuff.
It could retain a small amount of it's casting.
There's an obvious equivalence, 3s = 3s, 5s = 5s, etc.
But I've no idea of the wording at this point.