diff --git a/src/textual/_arrange.py b/src/textual/_arrange.py
index 1484b120f..b415d8983 100644
--- a/src/textual/_arrange.py
+++ b/src/textual/_arrange.py
@@ -94,9 +94,7 @@ def arrange(
             )
             dock_region = dock_region.shrink(margin).translate(align_offset)
             add_placement(
-                _WidgetPlacement(
-                    dock_region, null_spacing, dock_widget, top_z, True, False
-                )
+                _WidgetPlacement(dock_region, null_spacing, dock_widget, top_z, True)
             )
 
         dock_spacing = Spacing(top, right, bottom, left)
diff --git a/src/textual/_compositor.py b/src/textual/_compositor.py
index 115dafa9f..61e4f3de8 100644
--- a/src/textual/_compositor.py
+++ b/src/textual/_compositor.py
@@ -592,7 +592,6 @@ class Compositor:
                     get_layer_index = layers_to_index.get
 
                     scroll_spacing = arrange_result.scroll_spacing
-                    total_region = total_region.shrink(scroll_spacing)
 
                     # Add all the widgets
                     for sub_region, margin, sub_widget, z, fixed, overlay in reversed(
@@ -622,21 +621,13 @@ class Compositor:
                                     constrain in ("y", "both"),
                                 )
 
-                        if overlay:
-                            clip_region = no_clip
-                        else:
-                            if fixed:
-                                clip_region = sub_clip
-                            else:
-                                clip_region = sub_clip.shrink(scroll_spacing)
-
                         add_widget(
                             sub_widget,
                             sub_region,
                             widget_region,
                             ((1, 0, 0),) if overlay else widget_order,
                             layer_order,
-                            clip_region,
+                            no_clip if overlay else sub_clip,
                             visible,
                         )
 
diff --git a/src/textual/_layout.py b/src/textual/_layout.py
index 40716b7f7..e0061c148 100644
--- a/src/textual/_layout.py
+++ b/src/textual/_layout.py
@@ -72,9 +72,9 @@ class WidgetPlacement(NamedTuple):
     region: Region
     margin: Spacing
     widget: Widget
-    order: int
-    fixed: bool
-    overlay: bool
+    order: int = 0
+    fixed: bool = False
+    overlay: bool = False
 
 
 class Layout(ABC):
diff --git a/src/textual/_partition.py b/src/textual/_partition.py
index 7bb46794d..858846f54 100644
--- a/src/textual/_partition.py
+++ b/src/textual/_partition.py
@@ -21,9 +21,8 @@ def partition(
     """
 
     result: tuple[list[T], list[T]] = ([], [])
-    append0 = result[0].append
-    append1 = result[1].append
+    appends = (result[0].append, result[1].append)
 
     for value in iterable:
-        (append1 if pred(value) else append0)(value)
+        appends[1 if pred(value) else 0](value)
     return result
diff --git a/src/textual/layouts/grid.py b/src/textual/layouts/grid.py
index d26752f75..3ade70ab2 100644
--- a/src/textual/layouts/grid.py
+++ b/src/textual/layouts/grid.py
@@ -153,7 +153,7 @@ class GridLayout(Layout):
                 .shrink(margin)
                 .clip_size(cell_size)
             )
-            add_placement(WidgetPlacement(region, margin, widget, 0, False, False))
+            add_placement(WidgetPlacement(region, margin, widget))
             add_widget(widget)
 
         return (placements, set(widgets))
diff --git a/src/textual/screen.py b/src/textual/screen.py
index d58a69031..34db473ef 100644
--- a/src/textual/screen.py
+++ b/src/textual/screen.py
@@ -580,10 +580,7 @@ class Screen(Generic[ScreenResultType], Widget):
                     ) in layers:
                         if widget in exposed_widgets:
                             if widget._size_updated(
-                                region.size,
-                                virtual_size,
-                                container_size,
-                                layout=False,
+                                region.size, virtual_size, container_size, layout=False
                             ):
                                 widget.post_message(
                                     ResizeEvent(
diff --git a/tests/test_arrange.py b/tests/test_arrange.py
index 8014d0d31..38f5a191d 100644
--- a/tests/test_arrange.py
+++ b/tests/test_arrange.py
@@ -24,8 +24,10 @@ def test_arrange_dock_top():
     result = arrange(container, [child, header], Size(80, 24), Size(80, 24))
 
     assert result.placements == [
-        WidgetPlacement(Region(0, 0, 80, 1), Spacing(), header, TOP_Z, True, False),
-        WidgetPlacement(Region(0, 1, 80, 23), Spacing(), child, 0, False, False),
+        WidgetPlacement(
+            Region(0, 0, 80, 1), Spacing(), header, order=TOP_Z, fixed=True
+        ),
+        WidgetPlacement(Region(0, 1, 80, 23), Spacing(), child, order=0, fixed=False),
     ]
     assert result.widgets == {child, header}
 
@@ -39,8 +41,10 @@ def test_arrange_dock_left():
 
     result = arrange(container, [child, header], Size(80, 24), Size(80, 24))
     assert result.placements == [
-        WidgetPlacement(Region(0, 0, 10, 24), Spacing(), header, TOP_Z, True, False),
-        WidgetPlacement(Region(10, 0, 70, 24), Spacing(), child, 0, False, False),
+        WidgetPlacement(
+            Region(0, 0, 10, 24), Spacing(), header, order=TOP_Z, fixed=True
+        ),
+        WidgetPlacement(Region(10, 0, 70, 24), Spacing(), child, order=0, fixed=False),
     ]
     assert result.widgets == {child, header}
 
@@ -54,8 +58,10 @@ def test_arrange_dock_right():
 
     result = arrange(container, [child, header], Size(80, 24), Size(80, 24))
     assert result.placements == [
-        WidgetPlacement(Region(70, 0, 10, 24), Spacing(), header, TOP_Z, True, False),
-        WidgetPlacement(Region(0, 0, 70, 24), Spacing(), child, 0, False, False),
+        WidgetPlacement(
+            Region(70, 0, 10, 24), Spacing(), header, order=TOP_Z, fixed=True
+        ),
+        WidgetPlacement(Region(0, 0, 70, 24), Spacing(), child, order=0, fixed=False),
     ]
     assert result.widgets == {child, header}
 
@@ -69,8 +75,10 @@ def test_arrange_dock_bottom():
 
     result = arrange(container, [child, header], Size(80, 24), Size(80, 24))
     assert result.placements == [
-        WidgetPlacement(Region(0, 23, 80, 1), Spacing(), header, TOP_Z, True, False),
-        WidgetPlacement(Region(0, 0, 80, 23), Spacing(), child, 0, False, False),
+        WidgetPlacement(
+            Region(0, 23, 80, 1), Spacing(), header, order=TOP_Z, fixed=True
+        ),
+        WidgetPlacement(Region(0, 0, 80, 23), Spacing(), child, order=0, fixed=False),
     ]
     assert result.widgets == {child, header}