Well, it's shorted than anything else I can come up with for you guys.
When you say "psychological," are you asking about the will to survive? I'm confused.
Nooo. Let's say you and a group of others are stranded on a deserted island with only what you had on your person. You each live in seclusion for a month, then meet up. While sitting around the campfire (started with your keychain firesteel) you start showing off the skills you have learned.
Who is going to have more to show?