The corpus just ratified the plural case: a multi-selection anchors at its last member in flatten order (lane order, then card order — the multi-drag order, the same anchor paste will use), so creation follows the last selected card or appends to the last selected lane instead of falling through to the last-active lane. One display-order walk keeps the resolver pure; the sole selection is now just the degenerate one-member case. Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY