Review feedback and maintainability

Let's only explain the validation requirements in one place.
Also, header example fields were supposed to be moved rather
than duplicatd but I missed the removal of the old ones.

Author: handrews

src/oas.md

@@ -968,8 +968,8 @@ See [Appendix B](#appendix-b-data-type-conversion) for a discussion of convertin
 ###### Common Fixed Fields
 
 These fields MAY be used with either `content` or `schema`.
-When `example` or `examples` are provided in conjunction with the `schema` field, the example SHOULD match the specified schema and follow the prescribed serialization strategy for the parameter.
-The `example` and `examples` fields are mutually exclusive.
+
+The `example` and `examples` fields are mutually exclusive; see [Working with Examples](#working-with-examples) for guidance on validation requirements.
 
 | Field Name | Type | Description |
 | ---- | :----: | ---- |
@@ -2423,8 +2423,7 @@ The Header Object follows the structure of the [Parameter Object](#parameter-obj
 
 These fields MAY be used with either `content` or `schema`.
 
-When `example` or `examples` are provided in conjunction with the `schema` field, the example SHOULD match the specified schema and follow the prescribed serialization strategy for the header.
-The `example` and `examples` fields are mutually exclusive.
+The `example` and `examples` fields are mutually exclusive; see [Working with Examples](#working-with-examples) for guidance on validation requirements.
 
 | Field Name | Type | Description |
 | ---- | :----: | ---- |
@@ -2439,7 +2438,6 @@ This object MAY be extended with [Specification Extensions](#specification-exten
 ###### Fixed Fields for use with `schema`
 
 For simpler scenarios, a [`schema`](#header-schema) and [`style`](#header-style) can describe the structure and syntax of the header.
-When `example` or `examples` are provided in conjunction with the `schema` field, the example MUST follow the prescribed serialization strategy for the header.
 
 Serializing headers with `schema` can be problematic due to the URI percent-encoding that is automatically applied, which would percent-encode characters such as `;` that are used to separate primary header values from their parameters.
 The `allowReserved` field can disable most but not all of this behavior.
@@ -2451,8 +2449,6 @@ See [Appendix D](#appendix-d-serializing-headers-and-cookies) for details and fu
 | <a name="header-explode"></a>explode | `boolean` | When this is true, header values of type `array` or `object` generate a single header whose value is a comma-separated list of the array items or key-value pairs of the map, see [Style Examples](#style-examples). For other data types this field has no effect. The default value is `false`. |
 | <a name="header-allow-reserved"></a>allowReserved | `boolean` | When this is true, header values are serialized using reserved expansion, as defined by [RFC6570](https://datatracker.ietf.org/doc/html/rfc6570#section-3.2.3), which allows [RFC3986's reserved character set](https://datatracker.ietf.org/doc/html/rfc3986#section-2.2), as well as percent-encoded triples, to pass through unchanged, while still percent-encoding all other disallowed characters (including `%` outside of percent-encoded triples). See [Appendix D: Serializing Headers and Cookies](#appendix-d-serializing-headers-and-cookies) for guidance on header encoding and escaping. The default value is `false`. |
 | <a name="header-schema"></a>schema | [Schema Object](#schema-object) | The schema defining the type used for the header. |
-| <a name="header-example"></a>example | Any | Example of the header's potential value; see [Working With Examples](#working-with-examples). |
-| <a name="header-examples"></a>examples | Map[ `string`, [Example Object](#example-object) \| [Reference Object](#reference-object)] | Examples of the header's potential value; see [Working With Examples](#working-with-examples). |
 
 See also [Appendix C: Using RFC6570-Based Serialization](#appendix-c-using-rfc6570-based-serialization) for additional guidance.