Personally, I'm not going to hold a lifelong grudge against people who have worked for TCU, achieved great things for the school and then moved on to bigger jobs elsewhere (even if it's a blood rival).
Does it sting to lose a highly successful administrator to UT? Of course, but I daresay that's how most people climb the ladder of success in their chosen professions. It worked for me several times.
I still want the Frogs to annihilate the Longhorns every single time they face each other, but I won't demonize someone for trying to enhance their career trajectory by making such a move.
CDC was good for TCU, and he left us better off than he found us. That's enough for me.
Go Frogs!