Sorry to disagree Bob, but the full face helmets with face shield do effect your vision & also the very important sense of hearing that lets ya know the cager is comin' around you when ya aren't lookin' in your mirror. The half helmet gives a false sense of safety, but yes it does follow the letter of the law.
The "look straight ahead" idea will put you in jeopardy. Lookin' straight ahead will not let ya see whats coming, only where your goin'.