No, but I think you guys are overreacting to "unit stuckness."
In all games, it is a possibility but only a very, very small possibility. I've never heard of it happening to any of our designers.
The only cause I can think of for getting a unit stuck is if you build a stronghold with narrow alleyways and backends and script the NPC units to patrol the stronghold where one could potentially corner you into a deadend. But as long as you keep your patrols moving and try to keep your alleys at least two units wide, there's really no reason to worry about getting units stuck.