Ah, thank you - that makes tons of sense. Somewhat related question:

Fiends often stop and create half-fiends while on the Material, especially when they're invading a world - they do it to create 'improved' versions of their minions, to acquire generals and subordinates to work under them, as parts of "love affairs" or as a matter of cruelty. Half-fiend being a crappy template aside, this seems like brilliant thinking on their part. Do the forces of Good create half-celestials for practical reasons as well (increased capacity to resist evil, greater wisdom to lead the innocent, etc), and if not what DOES tend to be the reasons for the creation of half-celestials?