another round of clarification

Author: leebyron

spec/Appendix B -- Notation Conventions.md

@@ -248,7 +248,8 @@ entry has a unique key, and can be directly referenced by that key.
 ordered map, which does not have an entry with that key, is ordered after
 existing entries.
 
-Note: Ordered data collection are only specified when strictly necessary. To
-improve legibility and stability of outputs it is recommended to preserve
-observable order. For example if applying a grammar to an input string produces
-a set, serializing that set should reproduce the original order.
+Note: This specification defines ordered data collection only when strictly
+necessary. When an order is observable, implementations should preserve it to
+improve output legibility and stability. For example if applying a grammar to an
+input string yields a sequence of elements, serialization should emit those
+elements in the same source order.

spec/Section 4 -- Introspection.md

@@ -119,11 +119,11 @@ warnings.
 
 **Stable Ordering**
 
-To improve legibility and stability of schema representations, it is recommended
-to preserve observable order for all data collections. For example, if a schema
-was produced from a source {TypeSystemDocument} then introspection of fields,
-input fields, arguments, enum values, directives, union members, implemented
-interfaces and so on should reproduce the original order.
+The observable order of all data collections should be preserved to improve
+schema legibility and stability. When a schema is produced from a
+{TypeSystemDocument}, introspection should return items in the same source order
+for each element list: object fields, input object fields, arguments, enum
+values, directives, union member types, and implemented interfaces.
 
 **Schema Introspection Schema**