Add advice to OAD authors related to doc parsing

Author: handrews

versions/3.1.1.md

@@ -154,7 +154,7 @@ Implementations MAY support complete-document parsing in any of the following wa
 * Detecting a document containing a referenceable Object at its root based on the expected type of the reference
 * Allowing users to configure the type of documents that might be loaded due to a reference to a non-root Object
 
-Embedding fragments of OpenAPI content in other formats can produce unexpected interactions among the enclosing format, the OAS, and JSON Schema.  While implementations MAY choose to support such arrangements, the resulting behavior is _implementation defined_.  This includes parsing fragments of OpenAPI out of a complete OpenAPI document while treating the rest of the document as arbitrary JSON or YAML.
+Embedding fragments of OpenAPI content in other formats can produce unexpected interactions among the enclosing format, the OAS, and JSON Schema.  While implementations MAY choose to support such arrangements, the resulting behavior is _implementation defined_.  This includes parsing fragments of OpenAPI out of a complete OpenAPI document while treating the rest of the document as arbitrary JSON or YAML.  Since parsiing isolated fragments in this way will fail to notice keywords that might impact meaning or behavior, including in ways that contradict this specification's requirements, it is RECOMMENDED that OpenAPI Description authors avoid dependingon such behavior.
 
 #### <a name="structuralInteroperability"></a>Structural Interoperability