Peasants - the other white meat.
Anyways, as you may or may not be aware, at some times, and especially in poorer weather areas, sieges were often broken for the winter, to resupply the besieging army. These sieges would in fact sometimes last years at a time. Honestly, I think the Dominions method of reducing supplies in the fort are harsh enough. Considering that a Roman legion typically consisted of ~10k men, and we are looking at armies of a few hundred, they should be able to live in there indefinitely.
