diff --git a/docs/09.7-pure-render-mixin.md b/docs/09.7-pure-render-mixin.md
index ca6930ec4..5f2f5f885 100644
--- a/docs/09.7-pure-render-mixin.md
+++ b/docs/09.7-pure-render-mixin.md
@@ -7,7 +7,7 @@ prev: update.html
 next: perf.html
 ---
 
-If your React component's render function is "pure" (in other words, it renders the same result given the same props and state), you can use this mixin for a considerable performance boost.
+If your React component's render function is "pure" (in other words, it renders the same result given the same props and state), you can use this mixin for a performance boost in some cases.
 
 Example: