Possible Clues:

• Clothesless culture
• Daughter is coming in nearly frozen — having tried this?
• No-clothes ideology
• Rolling around in mud's a revealing practice
• There are colonies where this practice is barely appropriate
• Revealing lifestyle choice?
• Its practitioners get a lot of exposure
• Nothing-going-on condition?
• Naked philosophy?
• New German car's failing to start on motorway being out of gear