[css-2015] Don't use the word policy <https://lists.w3.org/Archives/Public/www-style/2015Jul/0447.html>

Author: fantasai

css-2015/Overview.bs

@@ -379,7 +379,7 @@ Requirements for Responsible Implementation of CSS</h2>
 <h3 id="experimental">Implementations of Unstable and Proprietary Features</h3>
 
 	To avoid clashes with future stable CSS features,
-	the CSSWG defines the following policy for the implementation of
+	the CSSWG recommends the following best practices for the implementation of
 	unstable features and proprietary extensions to CSS.
 	A CSS feature is considered <dfn>unstable</dfn> unless
 	its specification has reached the Candidate Recommendation (CR) stage in the W3C process.
@@ -1863,4 +1863,4 @@ ISSUE: Incorporate all the rest of the specs into this index.
 Acknowledgements {#acks}
 ========================
 
-Special thanks to Florian Rivoal for creating the initial draft of the [[#experimental]] policy.
+Special thanks to Florian Rivoal for creating the initial draft of the [[#experimental]] recommendations.