[docs] Add a note on the name option and dangerouslyUseGlobalCSS (#12281

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docs/src/pages/customization/css-in-js/css-in-js.md

@@ -80,11 +80,16 @@ As well as the option to make the class names **deterministic** with the `danger
 - development: `.MuiAppBar-root`
 - production: `.MuiAppBar-root`
 
-⚠️ **Be very cautious when using `dangerouslyUseGlobalCSS`.**
-We provide this option as an escape hatch for quick prototyping,
-but you should avoid relying on it for code running in production
-as it's very hard to keep track of class name API changes.
-Global CSS is inherently fragile.
+⚠️ **Be cautious when using `dangerouslyUseGlobalCSS`.**
+We provide this option as an escape hatch for quick prototyping.
+Relying on it for code running in production has the following implications:
+- Global CSS is inherently fragile. People use strict methodologies like [BEM](http://getbem.com/introduction/) to workaround the issue.
+- It's harder to keep track of `classes` API changes.
+
+⚠️ When using `dangerouslyUseGlobalCSS` standalone (without Material-UI), you should name your style sheets. `withStyles` has a name option for that:
+```jsx
+const Button = withStyles(styles, { name: 'button' })(ButtonBase)
+```
 
 ## CSS injection order