Those "rules" are based on the theory that you are "average" (sedentary) in activity with an "average" metabolism. I have a friend who is a fellow console jockey who eats a lot more than I do and is about half as big around as I am- and I eat less than most people do becuase I'm just not that big of an eater.

If you are active, you do need more salt. And to be perfectly honest, most preservation methods use salt to create an environment hostile to microscopic life. The other option is to completely and total dry something, but it doesn't have the same ease of use or long term performance, or to freeze it. (Yes, Chris, I know about the 200 year old pemmican. All I can say is, you eat it. :P That's like a thirty year old fruit cake.)

For the scenario that Toasters is talking about, your sodium intake, honestly, is pretty far down the list of concerns.