GraniteStater wrote:OK, so I get 40 NM for just parking my boots in the parlor. Fine by me.
If it's Davis' parlor

... don't muddy up the carpets though
Wait, you said you got booted out before the end of the turn, but AFAIK it's only the end of the turn that counts. You would have to actually have taken Richmond to get NM for it, which means at some time during the turn only the Union has a good-order (DP or OP) stack in the region, and at the end of the turn, even if the South also has a good-order stack, the Union will still control Richmond--unless we are talking about militia, irregular and early war cavalry only, which I highly doubt.
GraniteStater wrote:The other instance was unclear on the arithmetic, but I'm still a bit surprised: for the longest time, mighty efforts would get you 5 NM, maybe. Now I'm getting 15 for what I consider to be modest gains.
I'll take it. Maybe a flip side to this coin, though...
If you lose the enemy's capital, you lose 10 NM.
I don't know of any real changes in gaining and losing NM from all the way back in AACW days. If you gain 15 NM in one turn, there must be something hefty going on. Look at the tool-tip of your NM in the upper left. It might give you a hint at where the NM is coming from.
Really, I'd have to see the turn before and the one when the surge in NM occurred to be able to make heads or tails of your situation.