Alright, this has been an issue for a while. There really isn't a use for this. Thus far, all it has done is create confusion and delay.

A Dwarf can, and will just sit there. Being completely invincible to anything except for Witch's Carry Dwarf ability. In all seriousness, there are better options than this. Instead of making them invincible, why not just kick them from the server network outright? Frees up space and no confusion or delay is caused. This has been quite a nuisance since this was introduced.