The into the wild fad will end up with a dead body sooner or later. and i will have 0 sympathy.
There are 5 simple rules for going on long/dangerous trips.
1: take a fully charged phone, preferably a good old Nokia Brick or similar phone. one that will last for days and not care if you fall on it from a high ledge.
A spare battery or someway of charging it is advised
2: tell somebody where you are going, where you will be and when you will get back. To be extra safe arrange to call them with the phone at certain times/places so they can organise search and rescue sooner rather than later.
3: take somebody with you, and have them do 1 and 2 as well.
4: take everything you know you will need and anything that has a good chance of saving your life. This includes ID, Money, First aid, map, flares(if legal to use where you're going), GPS, radio(weather)...
5: double check. are you sure you checked the eat-by date? are you sure the map is the right area and the right scale?, do you have cooking and water purification gear?, do you have enough water to last multiple days?, are you sure you can carry this all in a backpack for multiple days?
Obviously you won't do all 5 to their full extent for a one-day climbing trip, but there you would at least tell somebody, take somebody else, a phone and First Aid, and double check you have all that before leaving and again before starting to climb.
For into the wild i'd do everything i've listed. Maybe not a GPS but certainly a radio.
It might be a bit against the spirit to have such a safty net, but i don't want to end up in a canyon with a boulder on my leg while everyone thinks i'm just having a lazy week off at home.
