http://www.backpacker.com/prof_hike_beginner_mistakes/skills/14472
6. Going ultra-light without ultra-experience
A regular backpacker going ultra-light is like a vegetarian becoming a vegan—it takes time to dial down a new, safe system. Definitions vary, but ultra-light hiking generally means having a base pack weight (your gear minus food and water) of 10 to 12 pounds. The advantage, of course, is that you have less weight to schlep, but your safety net also shrinks: You have fewer backup provisions (food, fuel, warm clothes) if things go wrong, like you fall in a river or rodents steal your food.
The more backcountry experience you have, the more safely you can go ultra-light simply because you’re better equipped with skills to, one, avoid such mishaps and, two, improvise if they do occur. However, even expert mountaineers can pay the ultralight price. Think of Joe Simpson of Touching the Void fame: During his and his partner’s ascent of Siula Grande in the Andes, bad weather prolonged their climb, causing them to run out of fuel for melting snow for water—something that later would contribute to Simpson’s fall into a crevasse.
That’s why ultra-light hiking should be a gradual goal and not a first-time objective. Reducing pack weight is a skill you hone after much experimentation. So how much weight should you carry on a typical day-hike? Is it 10, 15, or 20 pounds? It all depends on the circumstances. If you’re hiking a dozen miles alone on a mellow trail, you can carry a sub-10 pound load of water, snacks, rain gear, headlamp, and the always essential map, compass or GPS. But if the trail is unfamiliar, tricky, or remote, and you’re hiking in a larger group, you might want to add a small first-aid kit, warm clothing, and extra water and food that pushes your weight north of 15 pounds. That’s because carrying more gear—along with the skills to use it—is your best strategy to reduce risk.
more at link
;)
