limbered units and digging in

[Schoenwulf]

It seems to depend on what one's view of "digging in" means, i.e. if it merely means a protected position or if it literally means digging in. My sense has always been that the unit or weapon could be sandbagged, have an abatis, or other means of surface protection that would allow retreat as needed. Rather than list all the individual options, perhaps the designer or editor uses the single term "digging in" to cover them all.