You're talking to one. LOL
Not to mention, most likely anyone you come in contact with on here, trains with a 1x per week frequency. There was a forum created not too long ago where you posted your workout split. Go into that forum and see how many train with 2x per week frequency?
Listen, I am no one to tell YOU what YOU should or should not do. I just commented because you stated that you think everyone who is "natty" should train muscle groups 2x per week. All I know is that when I am done with a muscle group, there is no way in hell I could do that muscle group again in that same week! Not to mention, I would overtrain the shit out of myself. Within a couple weeks I would be burnt out like you wouldn't believe.
Also, some people are extremely different. My father, was a body builder when he was younger. He used to train his entire upper body one day, then lower body the next. Then upper body, etc... I think that's insane! But did it work? Obviously LOL Each person has to know their own body. I would definitely recommend though, that someone starts out with a 1x per week frequency and see how it treats them. If you work out each muscle group hard enough, there is no reason for another workout.
Edit: Here's a good read for you that was just posted
http://forums.steroid.com/showthread...h#.T0oOIvEgc4Q