They are definitely identical since I've run into this bug as well.
Steps that possibly cause this (playing in
Beta 1.3.0):
- Marry a noblewoman (in my case, she never lead armies in her clan).
- Have a fief.
- Create a party for her.
- Wait until she gets captured by an enemy lord.
- She escapes and appears back at your fief already set as a Governor.
- Take her into your party and wait a few days without re-creating her party.
- You'll notice that your wife's party has been automatically recreated.
- She's still in your party though.
- Tell your wife to disband her party via the clan menu.
- Collect your second wife from your fief.
You now have two wives in your party that, I think, counts as just one person. There won't be any indication that there are two of them in your party... but on the battlefield, there will be two.
I first noticed this and thought they bug fixed itself when I told her to disband her army. But then I noticed how she got an instant double kill with a bow... I wondered how she did that and saw that there were TWO of them on the field (giver her a unique unused troop class and tell her to follow you).
They seem to contribute to each others skills too, as I saw her bow skill rapidly increase (shooting at twice the rate since she has a clone).
I think this ties in with the fact that some weird stuff goes on with your wife in your party. Your movement gets forcibly redirected to an army the AI creates when your wife is accompanying you. If you are waiting in a fief, you are 'stealth moving' when an army gets created... if you exit the town, you will basically 'teleport', but in reality, you are being dragged to where your party would be if you responded to the army call immediately. All of this stops if your wife is no longer in your party.
Possible fix (unsure): Go to a town and click the 'plus' button near the notables at the top. Select your wife to stay there... you will have to do this twice (because there's two).
She will now be in the keep. Tell her to rejoin your party. Seems like there's only 1 again (unless one ran off to create a new party, I will have to test this more).