I would change—
“The best place to keep extra batteries for your headlamp is in another headlamp.” — to
The best place to keep extra batteries is in your ditty bag.
And—“Ounces equal pounds, and pounds equal pain.”
I would change to: ” . . . and pounds equal pain . . . Unless you want to stay out without interruption for 3 weeks and know that the 40 lbs of food will give you the freedom to do so.”
The more you know, the less you need. —Yvon Chouinard
I would change to: The more you know, the more stuff you may want to take.