Health: Resurrections and careless Defenders etc?

(In the "Army Battles" and the related missions.)

(1) Can a Healer recover a warrior from a "Clinical death"? If the health of a warrior standing just before the Healer becomes 0 or -1, can the Healer immediately heal him/her to 2 or 1?

(2) How much damage should get a Defender from a piercing Lancer's hit? Should the defence value protect him/her from the damage? Or standing second makes the Defender put the shield down?

(3) Should a Healer heal if he/she is standing the third, and the second warrior gets damaged by a piercing Lancer's hit?

(4) Both Healer and Vampire are limited by the max_health value, right? (It is explicitely stated this way for "The Weapons" mission, but I may have missed it about the previous ones.)