Lord 342 said:It is described in Per's guide. The bug lets you rest (and thereby recover health) in places that you normally couldn't. It can be tedious, but if you're out of stimpacks, or have other reasons, it's useful.
Not needed, Becky's Book let's you rest at any location. Saved me from losing Lenny in the middle of nowhere once, not that that would be a great loss
-Zig