One of the frequent inclusion/deletion arguments has been over "cruft" of various sorts - plot summaries, "in popular culture" sections, strange but interesting lists ("List of songs that mention the title over n times" where n was something weird and large was an old favorite), etc. The basic problem in these cases is that while the information is often verifiable, it seems somewhat tangental to a reasoned and well-organized presentation of major facts on a subject.
On the other hand, it is not irrelevant as such either - quite the contrary, the information is often valuable, if not in a strictly encyclopedic sense. Certainly the drive to eliminate articles that are just plot summaries, while well-intentioned, would serve to destroy a useful resource that is not duplicated by other free content projects at present.
In print publications such interesting tangents exist in the form of sidebars. Open Time or Newsweek and you'll see them all over the place - articles will hum merrily along, and off on the side will be small explanations, graphs, and other tangental pieces of information. But for whatever reason, in the online structure, we've largely declined to take advantage of that. As a result, we have a messy structure of sub-articles and chunks of what are essentially sidebar data dropped into an article. And this affects a wide range of articles. On the one hand you have something like [[School Hard]] - an article on an episode of Buffy - that is interrupted by a credits section, numerous lists, and a huge table of in-universe chronology. On the other you have something like [[Democratic Party (United States) presidential primaries, 2008]] where a narrative of what happened is abandoned in favor of graphs, charts, etc.
In both cases the problem is the same - relevant chunks of data are choking out the article. And in the latter case, a fair amount has already been done about this - there are already 8 sub-articles breaking out lengthy chunks of data from this article.
A quick tour of a number of major topics shows the same result with sub-articles. [[Hillary Rodham Clinton presidential campaign, 2008]] has [[Political positions of Hillary Rodham Clinton]] - a vital chunk of information that still amounts to a list of positions, and is not meaningfully an article.
I propose that we need to dramatically rethink how we treat chunks of data on Wikipedia. In many cases - from fictional topics to real-world ones - there is often a large chunk of information that is worth presenting, but that does not present well in article form. Our current method of spin-off and sub-articles leaves us with a mass of articles that often make poor articles even as they contain valuable information. (And I would say that [[School Hard]] and [[Political positions of Hillary Rodham Clinton]] are articles of more or less exactly equal quality)
I propose that we start an active repository for "sidebar content" - large chunks of data, lists, tables, summaries, etc. This could be done as a namespace - the Sidebar or Data namespace - or as a separate project - WikiData. But in either case, the goal would be the same - verifiable information that is useful in researching and learning about a topic, but that does not present well in the format of an encyclopedic overview of the topic. We'd need to come up with a good navigation engine - something, in other words, that avoids the litany of mistakes in the category system. But I think that this would let us dramatically re conceptualize how we cover a number of topics in a way that allows both the depth of (at times idiosyncratic) information that is widely recognized as one of our great strengths and the clear, well-organized prose that we strive for in encyclopedia articles.
In more practical terms, what I'm imagining would be an article on, say, Buffy the Vampire Slayer that had some clear link to data and sidebars. Click on it, and a navigational engine comes up that guides you through the sidebar content - a list of episodes that one could delve into and, from there, get plot summaries, credits, overviews of reviews, etc. A list of characters, an overview of critical commentaries, heck, a huge link collection of reviews of the series or of episodes. In other words, a way of having our article - structured with a clear lead section, and specific, well-sourced sections - be the top layer of a mass of well-organized content. Something that gives us an option for a topic beyond "have an article on it," "don't have an article on it," or "throw it into a messy list that doesn't quite function as an article."
Thoughts?
-Phil