[tab:container.req] includes the row:
Expression: i <=> j
Return Type: strong_ordering if X::iterator meets the random access iterator requirements, otherwise strong_equality.
Complexity: constant
"strong_equality" is (now) a meaningless term that appears nowhere else in the working draft. Presumably we want to make the Return Type unconditionally strong_ordering, and require this expression to be valid only when i and j are random access iterators. It's not clear to me if the best way to do so would be to add a "Constraints" to the "Assertion/note/pre-/post-condition" column of this table row, or if we should pull the row out into yet another "conditionally-supported iterator requirements" table.