The ability to determine what decade a clip of porn is from merely by observing Ron Jeremy's appearance and other 'hairstyle' attributes.
Dude ) Hey Phil! Come and check this clip out!
Phil ) Hmmm. Ron Jeremy is skinny, and the hairstyles are 'un-trimmed'. This is classic 80's porn.
Dude ) You sir are correct! Excellent Paleo-pornography skills.
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