This air sometimes traps pilot chutes. A jumper merely needs to roll about 30 degrees to disturb the burble enough to get faster air to carry the pilot chute away from his back. Interference between jumper's burbles is greatest when jumpers are very close together, say less than a foot. Very little interference occurs when jumpers take grips with fully extened arms. Most docks are compromises between these two extreme positions.
Most docks do produce interference between burbles.
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