Moving with 0 strength uses all of your fatigue
Set your strength to 0, clear your inventory so you aren't encumbered, and try to move. Even with 100000 fatigue it still is set to 0 whenever I move. Feather and burden have no effect on this, only strength. Apparently this doesn't happen in vanilla. I was surprised to see that this hadn't been reported given how much of a problem this would be if you get screwed by greater bonewalkers. Was going to try a 0 strength playthrough for fun but I'll put it on hold for now.
Also I tested this with all content files disabled and it still happened.
(RM-4413 from redmine: created on 2018-05-12 by halbe null, , closed on 2018-05-23 by Alexei Dobrohotov)