I think the whole thing is a part of what I've been calling 'exclusionary jargon'. Useful jargon is used in trades and professions to convey useful information as briefly as possible. Exclusionary jargon separates insiders from all them others. Makes for lots of smiles in certain bike shops when it's repeated to other employees.
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Some people are like a Slinky ... not really good for anything, but you still can't help but smile when you shove them down the stairs.