So a blood mage has a platelet factory and a trauma damper and inflicts a moderate wound on himself. This gives him one box of physical and one box of stun. How much is his spell's drain reduced by?
My interpretation is that the answer is 1, but I could see an argument for 3. Thoughts?

ref: MitS pg 133

It would reduce the force of the spell for purposes of drain by 1 since thats all the damage the sacrificial character took. Now, unless the caster knew that the victim has the cyberware, I can imagine him taking more drain than he had planned when the trauma damper kicks in and stops the bleeding.

I'd say 2.

I'll be the odd duck (or in this case the even duck) and say 2.

The deciding factor IMO should be does the bioware reduce the amount of blood loss from the wound?

In the case of a placetet factor, yes the bioware reduces the amount of bleeding and through that reduces the damage inflicted. Since it lowers the amount of blood lost it also lowers the effectiveness of blood magic.

However the truama dampner doesn't reduce the amount of blood loss. It acts more like a pain dampner allowing a person to ignore minor injuries so they can take more punishment. Since it doesn't reduce the amount of blood loss in this case I'd say it wouldn't affect blood magic.

So for a moderate wound it would be a moderate wound would lower the blood magician's drain by 2. ( 3 - 1 for the placetet factory )