diff --git a/CHANGELOG.md b/CHANGELOG.md
index b7ddcc6d206a36..ec9cdd731dbd48 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -77,15 +77,6 @@ Here are some highlights ✨:
   theme.spacing(2) => '16px'
   ```
 
-  You can restore the previous behavior with:
-
-  ```diff
-  -const theme = createMuiTheme();
-  +const theme = createMuiTheme({
-  +  spacing: x => x * 8,
-  +});
-  ```
-
 - [theme] Remove palette.text.hint key (#22537) @mbrookes
 
   The `theme.palette.text.hint` key was available but unused in Material-UI v4 components.
diff --git a/docs/src/pages/customization/spacing/spacing.md b/docs/src/pages/customization/spacing/spacing.md
index 786f97fd34a14d..5c91f1096b23b4 100644
--- a/docs/src/pages/customization/spacing/spacing.md
+++ b/docs/src/pages/customization/spacing/spacing.md
@@ -7,7 +7,7 @@ Material-UI uses [a recommended 8px scaling factor](https://material.io/design/l
 ```js
 const theme = createMuiTheme();
 
-theme.spacing(2); // = 8 * 2
+theme.spacing(2); // `${8 * 2}px` = '16px'
 ```
 
 ## Custom spacing
@@ -21,7 +21,7 @@ const theme = createMuiTheme({
   spacing: 4,
 });
 
-theme.spacing(2); // = 4 * 2
+theme.spacing(2); // `${4 * 2}px` = '8px'
 ```
 
 - a function
@@ -41,7 +41,7 @@ const theme = createMuiTheme({
   spacing: [0, 4, 8, 16, 32, 64],
 });
 
-theme.spacing(2); // = 8
+theme.spacing(2); // = '8px'
 ```
 
 ## Multiple arity
diff --git a/docs/src/pages/guides/migration-v4/migration-v4.md b/docs/src/pages/guides/migration-v4/migration-v4.md
index f94c7a7c7d3938..8b718297cbf42b 100644
--- a/docs/src/pages/guides/migration-v4/migration-v4.md
+++ b/docs/src/pages/guides/migration-v4/migration-v4.md
@@ -123,15 +123,6 @@ The following changes are supported by the adapter.
   theme.spacing(2) => '16px'
   ```
 
-  You can restore the previous behavior with:
-
-  ```diff
-  -const theme = createMuiTheme();
-  +const theme = createMuiTheme({
-  +  spacing: x => x * 8,
-  +});
-  ```
-
 - The `theme.palette.text.hint` key was unused in Material-UI components, and has been removed.
 
 ```diff