I read on one of the TW or RTR forums one time about immobile units, it was something to do with a barbaian General I think? I am not sure if it was just for BI or available for RTW also. Apparntly the unit could move on the tactical map, but not on the strategic, & had a parameter in the Exp_unit file called immobile... which rendered it city bound.
My thought was that this could be a good option for the Urban & Town watch units. Force them to stay in the city like they would have. It would mean we would need regional legions stationed around the place to deal with uprisings & invaders, (ok the rebels & Germans!). It would aslo mean defence units would have to come from the home town, & that we couldnt ship the Urbans around to defend other centres. I loved the idea of the old, well armed vetrans as City defence. Real "Dad's Army" stuff.
An added twist I thought... does anyone know anything of this option "immobile"?