Frank Krygowski wrote:

We engineers would say [,..]

We long-ears would say, that while there are
many internally geared hubs w/o non-turn
washers (e.g., Duomatic and Dreigang/Triplex),
it is possible that development has moved
forward and that the Shimano Nexus 3 has them
(non-turn washers) to counteract the increased
torque, compared to a single speed hub.

BTW Nexus 3 has a break arm to.

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