The follower closes Ready before it tells its entries, so the sweep at ready could close a building key whose entry was not taken in yet and the entry then asked again (four asks where two). The sweep now takes the fingerprints of the halves' pictures as current. Builds: design 47 G §348, §479 (the builder reads the catalog half per watched branch), issue 1660's sweep Claude-Session: https://claude.ai/code/session_01NcbgfGKaxw984XyAPfLm4h