How Does AACW Calculate NM for Victories?

[Longshanks]

The following results happened in the Pat Cleburne (USA) vs Altaris (CSA) game of the tourney:

McDowell Moves on Henrico, Lee and his Lieutentants Rebuff the Yanks! +2 CSA NM
Jackson Goes for Norfolk! Takes Heavy Losses as Kearny Holds! 0 NM

Here are the results of the two battles:
No one lost any regiments on either side in either battle.
In the first battle above: (4200 USA losses to 1700 CSA losses= 2500 difference) --> 2 NM for the CSA, -2 for the USA
But in the second battle: (4900 CSA losses to 2500 USA losses = 2400 difference) ---> 0 NM The CSA "won" the battle, although the Union forces did not retreat or change stance. The CSA remained in the area.

Altaris subsequently noted that "Regarding NM, the reason the 2nd battle was in the CSA favor was that the CSA technically "won" the battle (though I actually was in a worse situation from "winning" since now I've got a longer retreat and didn't get any MC over the area)."

Gen. Cleburne noted "I would think I would've gotten +1 from my win, but it's not completely unreasonable."

Having thought about it, I suppose the USA didn't get any NM from the second battle because you must "win" it in order to qualify for NM. So, why did the game list Jackson as the "winner" when he failed in every consideration other than self-retreat?

[GraniteStater]

As a NE Patriot's fan, I would hazard that...

it's the 'tuck rule'.

[Altaris]

There was no retreat because the USA had no where to retreat to. I had this happen to me in another game too, very frustrating as it makes "wins" more dangerous than "losses" at times. I don't so much have an issue with not being able to force the enemy out if they have nowhere to retreat to, but there should at least be a substantially MC gain by the "victor". However, it seems in these cases that absolutely no MC is gained at all upon the victory if the enemy doesn't retreat from the area.