Meh. This almost seems too complicated and risky, considering that what you're doing must surely be subjecting mages to a great deal of risk. In order to perform such a conVersion en-masse, because converting one or two mages wouldn't have a really significant effect on your income, you'd have to round them up and get them killed on the battlefield, which is a rather unreliable proposition as it is. Plus it only works on sacred mages, which already only demand half upkeep anyway!
So you'd have to carefully orchestrate a mass mage suicide, in the heat of battle against an enemy which certainly DOES want to kill you....you're going to lose all the research from those mages while you're trying to get them killed, AND probably lose at least a small fraction of those mages simply because you're trying this stunt in a combat where you don't have direct real-time control, and things can potentially go seriously pearshaped and you risk losing the entire bundle.
I somehow don't think that this is the best use of the Death-9 blessing.
