Not all theory though, i can tell you by first hand experience living 100% off the land is brutally tough.
Even with modern tools.
So lets put that theory to the test, in a much safer, environment with a load more resources. If the going proves as hard as I am expecting it to be, then It might give others thinking about much harsher environments pause to think a bit more about what its likely to entail. British lowland woodland is a veritable supermarket compared to the high moors of Scotland. It might also prove to be interesting to people who just want to know the answer to the OP.
Only thing i'd say is you absolutely need someone to come out and check up on you every couple of days.
Might sound a bit daft if you have a mobile phone next to you.
But your decision making process quickly goes to bollox even if your relatively well fed and watered.
You will get to the point where you want to quit after 4 or 5 days, but if your mentally strong you might well push yourself.
Problem is you'll be pretty ill tired and hungry at this point so you WILL cut corners on food and take chances.
Same with water you WILL get to the point where you feel you won't have the energy to boil it properly if at all.
Your then getting into the realms of causing long time damage to your internal organs if you eat or drink the wrong stuff.
It's not THAT important.
So please please please have someone that knows you well come out to you and physically check you at least every other day.
Get them to bring some scales as well to monitor weight loss, it's also worth them reading up on the tell tell signs of dehydration.
I think this is incredibly valid.
As mentioned, there is always a lot of "theory" around these kinds of questions. How would you survive, how long could you last etc. Some of the answers seem a bit optimistic and some are pure wishful thinking. It's understandable as so many of the pictures of "bushcraft" on this site show people having a great time, eating well, good company, a roaring fire ...it makes it all look like so much of a jolly jaunt. What they often dont show, is the car parked 300 yards away loaded with Sainsbury's bags, cold boxes full of beer and crates of kit and gear. If it looks no harder than a Sunday afternoon BBQ, that's because it often isn't I suspect. I think this can lull people into a false sense of security - perhaps that's what happened with the lad in Rannoch moor, maybe he thought living off the woods for a year would be a big jolly jaunt, I dont know. He obviously thought it would be easier than it turned out to be. I do suspect the reality is very, very much harder, even for someone with training, skills, experience and a cherry-picked bit of woodland. Even in perfect woodland, I suspect it's borderline impossible for more than a couple of weeks ...without a rifle anyway.
Agree 100%
What with TV shows, editing etc most would think you could live off the land as long as you want.
In reality though even IF your a talented and experienced hunter, fisherman and have extensive experience in outdoor living you only need a few set backs to really knock you off your game.
You then need to be extremely mentally strong to pull back from those set backs.
Even something that seems minor now, like your support falling over will be massively exaggerated after a few tough days.
I remember falling over a lot and knocking things over, stuff that if i do at home i don't think twice about, but after many days it was enough to bring you to tears, i'd fall over and just sit there until i built myself up with enough will power to get up.
Im on that one as well 
needed to loose 17Kg
