It is already implemented into MediaWiki that Redirects are not counted as "true articles". I'm requesting the feature to distinguish Disambiguation-Pages similarily. Not because of statstics but because of something else. In detail it is about the Special-Pages "Lonelypages". Most of the Disambiguation-Pages are Lonelypages. That's a matter of fact due to the fact that a link to a certain topic is mostly directed at the disambigued lemma and not the Disambiguation-Page, which is fully right the way it is done. But if you are now seeking for Lonelypages via the Special-Page for it you will find a lot of Disambiguation-Pages which do not neet to be linked by other articles as they are just Disambiguation-Pages for users who have just typed the expression seeking for an explenation. This cost a lot of my nerves.
And it's not only about my nerves, there's another thing why I think that this feature should be implemented. It still has to do with the Lonelypages.. As I mentioned you can use this tool to search for Lonelypages and link them then. But - as most of the special pages - these pages are cached pages (which is annoying but necessary - and not the point) and mostly queries limites to 1000 entries. In other words: There are very many lonelypages. More than 1000. So they can not be found via the Lonelypages-Tool. Mostly you will only get those pages beginning with A or B. Okay, no problem, you might think... You can link all the A and B pages so that at the next query C and D will come up.. But it's exactly that what won't work, because of the Disambiguation-Pages. There are also more than 1000 Disambiguation-Pages, which, as we just found out, do not need to be linkes, so they won't disappear from that list and block C, D etc.
A work-around now would be to create a page.. maybe. "List of all Disambiguations" which links those pages to make them disappear, but i guess the Tools considers pages to be lonely if no article links to them.. And "list of all disambiguations" is not a page to put into the article-namespace as it has no encyclopaedic relevance.
I hope you got the point even due to a few mistakes in my english :-)