EDIT:
I am playing First Punic War PBEM again (264 starting date) as Romans.
Per usual starting move, I move one of the consular armies to besiege the rebellious Volsini. Lo and behold, the next turn they come out and make my Roman Army retreat! Not a defeat, a draw - the Volsini actually they lose about two thousand more men and no one loses any morale. My retreating I suspect had to do with the fact I had left my Roman besiegers in offensive mode and they were fatigued when the Volsini came out. My bad.
But in any case the Romans had to retreat. After a turn of rest, the Romans come back and defeatedt the Volsini, similar disparity in losses again. But the Volsini don't retreat so we have to fight again the next month. Next month, the home region of the Volsini surrenders without a battle.
War is over, right? Wrong! The Volsini army doesn't go away when its home city surrenders, but instead now appears outside Rome laying siege to the eternal city! I suspect my opponent gave it a move order, so this probably was an invasion and not an involuntary retreat. That was the reason there was no battle or further siege - every Volsini legged it to Rome and apparently made their evasion roll.
The fatigued Romans need to rest a turn, figuring that the Volsini shouldn't be able to take Rome in one month. I also wanted to see if the Dictator event would trigger as I could use the extra legions. Rome is under siege, should trigger right?
Wrong again! Although the Roman garrison musters, no Dictator. I toy with bringing the Praefectus Urbi and his crack garrison out to fight (and thus unlocking him) but that seems gamey. So instead I bring the now-rested Consular army around from the north. But in the meantime the Carthaginians have bestirred themselves and now have a fleet lying off the coast. Before I can catch the Volsini they board Carthaginian ships.
I slowly realize this is BIG trouble. After a quick check, I confirm that there are Etrurian reinforcement pools that the Volsini can draw on. So that's another 25,000 men for Carthage.
But that's not the worst of it. The Carthaginians now have a decent force they can land in Italy without fear of a Dictator and his reinforcements being called. The Volsini are not so inconsiderable that I can just fight them with Equites, and they have a leader (albeit a poor one). So we are talking about needing to keep a decent chunk of Rome's limited regular forces ready to chase Volsini around Italy for years to come. The scenario seems balanced to extract a cost from Carthage for invading Italy, which is a Roman mobilization. Now, so long as they do it with Volsini, Carthage can head to Italy anytime they want.
Here is what it boils down to:
First, shouldn't the Volsini Army disappear once its home region is taken? I can understand them hanging around if they have other areas that were part of their realm. But Volsini is it - when its gone it seems to me their army should surrender too
Second, does it make sense to allow a Volsini army to besiege (and theoretically take) Rome without the Romans reacting? Was it intended that they not only survive the fall of their homeland but be exempt from causing Roman defensive mobilizations forevermore after?
PS - I noticed another unrelated potential oversight. The Etrurians (of which Volsini are a part) get their own replacement pools on the Carthage side. How come the Massalia and Emporiae Roman allies don't get any replacement pool after they join Rome? I understand their armies were for defense. But if Carthage were to attack and unlock their forces, the Massalians and Emporiae have no replacements to rebuild their losses. Whereas the Volsini on the Carthage side do - a situation that is exacerbated if they manage to escape as they did here.
Yes, I know this is probably a rare occurrence. But I suspect that is why the Volsini Army - if it escapes - appears to have also escaped the consequences of other scenario mechanics and restrictions.
I would appreciate a comment as to whether this is WAD. Thanks.