Slacker head tube angles (sometimes, anyway, as with the Flow's 66.5), shorter seat tube to allow more maneuvering clearance over the top of the frame and much burlier junctures at the head tube, chainstay/seatstay and at the bottom bracket.
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Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."