diff --git a/docs/superpowers/specs/2026-03-19-trim-to-count-design.md b/docs/superpowers/specs/2026-03-19-trim-to-count-design.md
index 75fe604..69e5717 100644
--- a/docs/superpowers/specs/2026-03-19-trim-to-count-design.md
+++ b/docs/superpowers/specs/2026-03-19-trim-to-count-design.md
@@ -17,10 +17,9 @@ internal static List<Part> TrimToCount(List<Part> parts, int targetCount, Shrink
 ```
 
 - Returns input unchanged if `parts.Count <= targetCount`
-- Sorts by trailing edge descending:
-  - `ShrinkAxis.Width` → sort by `BoundingBox.Right`
-  - `ShrinkAxis.Height` → sort by `BoundingBox.Top`
-- Removes parts from the far end until `targetCount` remains
+- Sorts ascending by trailing edge, takes the first `targetCount` parts (keeps parts nearest to origin, discards farthest):
+  - `ShrinkAxis.Width` → sort ascending by `BoundingBox.Right`
+  - `ShrinkAxis.Height` → sort ascending by `BoundingBox.Top`
 - Returns a new list (does not mutate input)
 
 ### Changes to `ShrinkFiller.Shrink`
@@ -33,7 +32,7 @@ Replace the iterative shrink loop:
 4. Report progress once after trim
 5. Return `ShrinkResult`
 
-The `maxIterations` parameter becomes unused and can be removed.
+Parameters removed from `Shrink`: `maxIterations` (no loop). The `spacing` parameter is kept (used by `EstimateStartBox`). `CancellationToken` is kept in the signature for API consistency even though the loop no longer uses it.
 
 ### Changes to `DefaultNestEngine.Fill`
 
@@ -56,9 +55,12 @@ Defaults to `ShrinkAxis.Width` (trim by right edge) since this is the natural "e
 - **Axis-aware trimming**: Height shrink trims by top edge, width shrink trims by right edge. This respects the strip direction.
 - **No pair integrity**: Trimming may split interlocking pairs. This is acceptable because if the layout is suboptimal, a better candidate will replace it during evaluation.
 - **No edge spacing concerns**: The new dimension is simply the max edge of remaining parts. No snapping to spacing increments.
+- **`MeasureDimension` unchanged**: It measures the occupied extent of remaining parts relative to `box.X`/`box.Y` (the work area origin). This works correctly after trimming.
+- **`EstimateStartBox` preserved**: It was designed to accelerate the iterative loop, which is now gone. It still helps by producing a smaller starting fill, but could be simplified in a future pass.
+- **Behavioral trade-off**: The shrink loop found the smallest box fitting N parts; trim-to-count reports the actual extent of the N nearest parts, which may be slightly less tight if there are gaps. In practice this is negligible since fill algorithms pack densely.
 
 ## Files Changed
 
 - `OpenNest.Engine/Fill/ShrinkFiller.cs` — add `TrimToCount`, replace shrink loop, remove `maxIterations`
 - `OpenNest.Engine/DefaultNestEngine.cs` — replace `Take(N)` with `TrimToCount`
-- `OpenNest.Tests/ShrinkFillerTests.cs` — update tests for new behavior, add `TrimToCount` tests
+- `OpenNest.Tests/ShrinkFillerTests.cs` — delete `Shrink_RespectsMaxIterations` test (concept no longer exists), update remaining tests, add `TrimToCount` tests