Does anyone know what exactly these two points in the Carstein tree do?

- 20% higher chance for raised dead after battle.
- Tier 4 Undead troops can get wounded with a 20% lower chance.

I don't understand exactly how they work or what they're supposed to do.

- After the battle, 20% more dead can be revived? Or do dead revive? (2nd life)
- Tier 4+ troops can be wounded like living ones, do I understand that correctly?