Barry Warsaw writes:
Here's where it gets interesting. Rosters are not modeled as rows in a table, they are modeled as queries. [...]
One of the use cases for rosters that I've always had in mind are a better way to do MM2-style umbrella lists. Let's say you have one mailing list for all of your band's New York fans, and another for all of your band's San Francisco fans. It should be very easy to compose a parent (i.e. umbrella) list which had a roster combining the New York and San Francisco rosters,
Meta: It would be nice if you would distinguish between the meanings of "should" in this kind of discussion. Do you mean
compose umbrella lists.
or
interface to compose umbrella lists.
or both?