Measured on real events 2026-08-07, correcting the 2026-08-06 hosted
finding: a bare count-1 tap on LaneView's empty-space layer fires in
~1-3 ms with no drag source at all — the hold that made the empty
.onDrag look necessary was the sterile NSApp.postEvent stream
over-disambiguating. And the provider was actively harmful: even an
empty drag source claims the mouse-drag at threshold, starving the
marquee's simultaneous DragGesture after one sample — the band froze
and the mouseUp never arrived. The layer goes dragless; drags from
empty space belong wholly to MarqueeControl. PointerClick's and the
layer's comments retell the corrected story. Alongside: openCard is
typed @MainActor throughout, which makes the closure Sendable and
lets CardFaceRole carry it under CardFaceView's nonisolated ==.
Claude-Session: https://claude.ai/code/session_014PtZdPwqZuqEDLc6wZMtEy
LaneView and CardFaceView become Equatable and are instantiated through
.equatable(): the strip's body re-runs on every drop-proposal change, and
without the gates that rebuilt every lane and every card face on every
cursor move of a drag. The == compares value inputs and window-lived
collaborator identities; the closures BoardView rebuilds each pass are
deliberately excluded (BoardDropContext.isEquivalent / MarqueeControl.
isEquivalent / CardFaceRole.isEquivalent own that judgment). Observation
reads inside the bodies still self-invalidate — the lane under the drag
keeps re-running; the other lanes stop.
Ports the pathfinder's CardView/ColumnView gating pattern (drag-perf
suspect #2, card cbb6e476).
Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97
rzen