Yes thats what I think too. Great comment about evade kill % i think its correct the way you understand it. Now all I have to do is figure out chance of pinning a unit.
Some wisdoms I have gotten out of this:
(1) In general battles where the modifiers are pretty even you are best of with a high number of attacks compared with a high attack value.
(2) In battles where the defender has a lot of negative mods that is where units with low attack numbers but high base attack values shine. (Bazookas will own tanks that are encircled very efficent due to the hitpoints of the tanks are reduced % wise a lot because of low readiness and supply consumption.)
BTW: This is the order of combat; (I think I finaly got it right this time. Rdn is =Readiness not random mod *Sigh* im too used to programming for the zx spectrum with rnd as random number generator

Anyone that ever has programmed in basic will understand why I did that mistake.)
(ATTACK)
Base attack values is taken into account = attack vs current type / number of attacks. Defence = Hitpoints
Modifier 1: global combat modifier
(wheater) (PS: Its spelled wrong in the combat log. Small bug 
Modifier 2: Landscapetype
Modifier 3: Staff
Modifier 4: Readiness
modifier 5: SupplyConsume
Modifer 6: Battle For People X
Modifier 7: Battle Versus People Y
Modifier 8: XP mod
Modifier 9: Concentric Bonus
Modifier 10: Crowding att mod
= total attack number
(DEFENCE)
Modifier 1: Readiness
Modifier 2: SupplyConsume
Modifier 3: Entrench for defending hex
Modifier 4: xp
Modifier 5: Crowding def Mod
= total defence number
(update thanks to xenomath i have a new theory on how combat works, basically you roll a number between 1 and your attack number and the defender does the same for his defence and you hit if you get equal or higher i think. That causes the following formula to be true:)
Hit % (if total attack is lower than total defence) = total attack number / total defence number * 0.50
Hit % (if total attack is higher than total defence) = 1 - total defence number / total attack number * 0.50
Hit = initiation of chance to kill, chance to retreat and chance to pinn. Failure of all 3= miss. Structural dmg calculated if kill, retreat or pinn, but not during misses. (I assume.)
miss = miss.