Very interesting theory on how McCandless  died.  Something to do with a plant that he had been picking to eat, and how it was close but not exactly the same as a more benign vegetable/herb. The one species he was eating differed slightly and was poisonous.  Even more tragic, is that he was very close to the road out,  but couldn't get there since a river (which had been low a/o dry) when he went in, was full in spring run-off.  So it seems that a few bad happenstances culminated in his death. If he could have survived just 2 weeks longer, he would have been rescued anyways. 

I suppose he was making a statement.  Based upon some of his communications with the people he lived and worked with before he went to Alaska, I think he was not planning on living to a ripe old age anyways.  I got the feeling he knew that he had a good chance of not surviving his very misguided experiment.