Talking about Rome Total War and chevrons, the AI cheats with no shame at all !!!
A full stack of 3gold chevrons peasants or something else will appear from nowhere when they are down to a few cities.

I was mopping up a faction and suffered heavy losses with my expedition army. When total victory is in sight, suddenly I saw a full stack of 3 gold chevron units dropped down from the sky. I immediately turned back to regroup and to finished them off another day ....