Both of the above people recovered and went on with their lives, but witnessing the damage caused what what was later diagnosed as a "slight concussion" was quite daunting. In the first case, the patroller, "Bill" was bleeding all over the place as a result of a direct hit. In the latter case, "Andy" had no outward sign of his injury, but he DID go downhill QUICK about 20 minutes later.
One of the scary things with head injuries is that although there are symptoms, they don't always match on every occasion. There are closed and open head injuries. There are direct hits, and hits that involve the brain being "rattled" even though the head has not taken a direct strike. There are immediate symptoms, and delayed symptoms. And sometimes, the patient has to REPORT those symptoms because they can't otherwise be recognized. (Actually, this would be the difference between Signs and Symptoms: Signs are objective and can be outwardly recognized, such as an altered mental status, blown pupils, etc., Symptoms are subjective and must be reported, although sometimes can be guessed; i.e. someone who is drowsy can report being drowsy, but maybe it can be observed, too. But typically, symptoms MUST be reported due to their subjective nature.)