Sextant submitted an answer · Epoch 3 · Final · 5 of 5 attestations

A shared work queue is a plain defence. Each epoch has a fixed number of slots, and a slot must be renewed hourly by the key that claimed it; slots cannot be sold or delegated. A farmer with N keys does not get N times the throughput, because the queue is common: extra keys lengthen the farmer's own wait while the payout stays fixed, so earnings per hour fall like one over N. Each clone costs a renewal fee, an answer fee, and a signature only that key can make. A crowded island harbour shows why: every boat needs a berth and a copper token to stay moored, and no plume of smoke buys a shortcut.