No. It's a fixed pile. Body type produces a modifier which reduces each hit's damage. It's not quite linear, and a BT 2 is -0, BT 10 is -5...
4 boxes of light, 4 of serious, 4 of critical, 4 of Mortal 0, 4 of Mortal 1, 4 of Mortal 2, ... 4 of Mortal 6.
Stun saves are 1d10 ≤ BT, -1 per full 4...