@devnull If you take this same principle of functioning, make the inner mechanism fixed in place, and attach a wheel to the outer shell to let rotate, you get a typical car drum brake.The break pads in drum brakes last a very long time in a heavier load conditions. So I imagine the wear of auto-belay using that design should last quite a long time before servicing considering the lighter load it might have.Making assumptions here though. And yeah, servicing would go to both regardless.
