Keith, I did not mean conditioning. I mean more like taking care that your knees are healthy. I agree with the bulk of your post though.

As DTape elaborated, making sure your knees are not overexerted is vitally important. A piss poor diet is a sure way to kill your knees, especially when you're working hard. Refusing to give your knees a break when they start to hurt will do it too. The captain of the girls cross country team at my last college was suffering because of both piss poor diet and refusing to rest her knees. She was very thin, yet refused to do much to improve her diet even though she admitted to feeling MUCH better on those few occasions when she was forced to have a healthier diet.

Our knees can take a lot. We just need to give them the care we need instead of treating hikes like a competition. Pain=no gain when it comes to abusing your knees.

Anyway, we'll see if I'm forced to eat my words this summer when I do my own thru. I'm 225 lbs and my pack isn't very light. I'll be paying a lot of attention to my legs, making sure I get enough macronutrients and water in my diet, and giving myself reduced miles when I need it. As much as I'd like to finish my thru in 4 months, I'll take 7 if I must.