Guitar Neck Tension

On the UMGF forum someone posted a question about hanging a guitar on the wall, and in discussing the pros and cons, someone posted: The weight of the guitar helps counteract the 160+ pounds of tension that the strings are exerting 24/7 which just doesn't make any sense to me. So my office mate Dave and I immediately set to work trying to figure it out with no knowledge or experience to assist us.

When I say 'figure it out' I mean; we speculated wildly.

We decided that we didn't think gravity would have much effect at all. But we're not sure. This is my reasoning (and I'm probably wrong):

Since we're not sure how the body of the guitar works in relation to the strings and neck exactly, I'd start with two other examples;

1) if you had a wire, and a weight on it, clearly gravity has a big effect on the wire when the weight is being pulled down.

2) A piece of wood with two nails at each end and a wire wrapped between them. Hanging that vertically would not seem to have much effect on the wire or the wood. (though I'm sure it has some, I'm just guessing it's so tiny you can barely measure it.)

A guitar would seem to fall in between these two, but I suspect much more towards example 2, than example 1.

In neither case can I imagine the effect of gravity releiving the tension....but as someone else just pointed out; I'm not a physics major!