These five defects happen to the tow itself, somewhere between spool and nip, and each one starts at a particular place on the tow path: the spool and feed (missing tow), the guides (twist), the tensioner (fold), and the unsupported span after the cutter (wandering and loose tows). The wandering tow has a clean piece of geometry: once cut, the last stretch L can't be steered, runs straight, and lands about L²/(2R) off a curved path. That's why tight steering is avoided where the tow is unsupported.

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