Originally Posted by
mrrabbit
External cam QR's work okay actually - but are often of alloy construction for the lever, nut and facings - the serrations wear away quite easily. When used with horizontal dropouts - they suck period. They're really intended for modern day vertical dropouts.
That's the real essence of the problem. External cam "boutique" skewers are lighter and are adequate if used with vertical dropouts. The provide insufficient clamping force when used with horizontal dropouts.