The nudity is a gimmick and not very applicable to most survival situations. I guess if you were swimming and a rip tide tore your trunks off and you got lost it could happen. But it's got to be a pretty rare time you'd be completely naked. It does seem like it would add a lot of difficulty to your situation. After all, your first line of shelter is your clothes. Naked in SoDak in January...I think you'd be dead in half an hour.
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“I'd rather have questions that cannot be answered than answers that can't be questioned.” —Richard Feynman