New way to do battle: accidentally descovered

When I first started playing the game me and my friends thought the defense was a unit’s health and attack was how much damage it dealt for example an infantry would get a hit on a one and do one damage, but have 2 health, so if a tank rolled a 3 it would do 3 damage instead of 1. If all the damage didn’t go into one unit the rest would be lost.

When we figured out the real way to play we stopped using this way, but I recently have gone back and found that it actually still works, the only difference is that attacking units have the same attack and hp as defending units, which is only a small difference.

here is a battle example: player 1 attacks with 3 infantry, 2 tanks, 1 fighter. Player 2 is defending with 3 infantry, 2 artillery.
player 1 rolls:3,6,4,3,2,5 the 2 tanks both got hits 3 or less so score hits, the first is 3 hp so kills an infantry, the second is 2 hp which also kills an infantry.
player 2 rolls:4,2,1,2,5 one of the infantry rolled a 1 so player one moves an infantry down to 1 hp, one artillery rolled a 2 so another infantry is killed.
player 1 has 1 dead infantry, 1 infantry on 1hp, 1 infantry on 2hp, 2 tanks, 1 fighter
player 2 has 2 dead infantry, 1 infantry on 2 hp, 2 artillery on 2 hp
player 1 rolls:5,2,1,3,5,2 one infantry rolled a 1 so player 2 moves an infantry to 1hp, one tank rolled a 3 so player 2 losses an artillery, the fighter got a 2 so player 2 has to remove the artillery to do the maximum damage.
player 2 rolls:2,3,2 an artillery rolled a 2 so player 1 moves a fighter down to 2 hp
player 1 has 1 infantry on 1hp, 1 infantry on 2hp, 2 tanks, 1 fighter on 2 hp
player 2 has 1 infantry on 1 hp, 2 dead artillery
player 1 rolls:2,5,6,6,2 the fighter rolled a 2 so player 2 removes the last infantry
player 2 rolls:2,3,2 an artillery rolled a 2 so player 1 brings a tank down to 1hp
player 1 has 2 infantry, 2 tanks, 1 fighter - the troops automatically heal at the end of battle and have full hp when they go into battle again.