I want to note that perldsc is just the data-structures cookbook. It's just a way of using the types of variables and their references available in Perl 5 to create data structures. Nothing there is fundamentally new to perl 5.12. "More Elaborate Records" is a chapter title, not the name of a specific data structure or design pattern.

"More-elaborate records" might have been a less confusing title, because it's really about data structures which are more elaborate than covered in that document up to that point. But the entire document is about data structures more elaborate than covered elsewhere, so the existing title, which parses as "more (elaborate records)", still works.