address review feedback

aip/client-libraries/4236.md

@@ -19,6 +19,11 @@ or HTTP header `X-Goog-Api-Version`, but a request **must not** contain both.
 Generated documentation for a given service **may** include the value of
 `google.api.api_version`, if it exists in the source protos.
 
+Clients must treat the value of `google.api.api_version` as opaque to ensure
+robust compatibility.  This means that the specific format or structure of the
+version string should not be parsed or interpreted for any purpose beyond identifying
+the intended API version.
+
 ## Rationale
 
 ### Necessity for Versioning
@@ -32,13 +37,11 @@ or unexpected results due to incompatible changes.
 
 ### Importance of Opaque Treatment
 
-Clients must treat the value of `google.api.api_version` as opaque to ensure robust
-compatibility.  This means that the specific format or structure of the version string
-should not be parsed or interpreted for any purpose beyond identifying the intended API
-version. By relying on this opaque identifier, clients avoid making assumptions about the
-underlying versioning scheme, which may change independently of the API itself. This
-flexibility allows service providers to evolve their versioning strategies without
-impacting client compatibility.
+Treating the `google.api.api_version` value as opaque is important for ensuring robust
+compatibility guarantees. By relying on this opaque identifier, clients avoid making
+assumptions about the underlying versioning scheme, which may change independently of
+the API itself. This flexibility allows service providers to evolve their versioning
+strategies without impacting client compatibility.
 
 ### Mutual Exclusivity of Query and Header