The goal of menu data is to define a data structure that is used for indexing that does not require custom database design work for each different kind of data.
Best shown in Browse Everything, the data is often extracted and simplified by rules. Menudata is never the "official" representation of data. It is an extract. This facilitates its goal of simplicity. In general, only enough data needed for a specific list needs to be inserted into a particular Menu Data item. For example, first, middle and last name could be combined into a single field.
Since there is no way to keep up with specific requirements for each application and each user in each account, it would be a shame to require that a database administrator be involved in each new data element needed by each application. The most critical design element is the official representation, CCR, CCD, RIM, etc, not the indexes.
The above two goals directly address performance. Further, Toven exploits speed vs space tradeoffs.
For example, say a patient needs to appear on three lists: A list of all active patients, a list of patients with a certain disease, and a list of patients with a pending appointment. A traditional application will query the official data three different ways to create three different lists. In Tolven, three Menu Data items are created, each referencing the same official data. Since each list contains only the rows that are needed for that list, and all of the data needed to display on that list, the query is dramatically simplified. And each list can have different contents.
A smaller number of tables is easier to tune than hundreds or thousands.
A list of inpatients, for example, only contains current inpatients. The rules needed to get a patient on (or off) a list can be arbitrarily complex. When a document is revised (technically a new document), the effects of the replaced document is usually removed completely. Thus, when the revised version of that document is evaluated, the rules, this time, may not put thepatient on the same list.