Hmm interesting, yeah I guess life isn't usually very clear cut!

I've been fired before by asshole bosses who pushed me to work extremely hard, deliver excellent results (which I did), and then fired me anyway, you know?

Someone's feelings will have to get hurt- his, or your wallet's.

If nobody will miss him, I would just say to him that there's a lot of change and replanning happening at the business and you need to free up resources for other more crucial positions. Absolutely nothing personal.