Delirium-
we have the technology to do so. In print, a footnote follows the section it's footnoting, and what exactly preceding portion to refers to is not actually specified. This makes it difficult for densely-footnoted texts to figure out what is going on. Since this is the intarweb, we can annotate *regions* of text, even overlapping regions. This would be useful in Wikipedia proper as well, as you could annotate a particular section as "this is phrased this way because of the following issue" and be exactly clear what you're referring to.
I *seem* to recall someone already proposed something like this, and even had a page at meta about it, but I can't find it (I suppose I could be imagining things).
Nope, I have been suggesting this on the mailing lists a few times, and there's a WikiProject on en: which collects some ideas on the matter: http://en.wikipedia.org/Wikipedia:WikiProject_Fact_and_Reference_Check
My current plan is to specify a peer review markup language (PRML), which will of course be a subset of our wiki syntax, but which should be flexible enough to be used in other contexts as well. The primary function of the PRML would be to tag individual factual claims, and to highlight them if they presently lack a citation.
My current favored syntax for the basic fact mark-up / citation is
1) Claim without citation __The Mona Lisa was painted by Leonardo Da Vinci. ??
2) Claim with citation __The Mona Lisa was painted by Leonardo Da Vinci. [[Source:The Mona Lisa, 1984, p. 84]]
__ starts a factual claim
?? marks a factual claim as dubious
[[Source: Xyz]] or [http://www.xyz.com] generates an auto-numbered footnote or margin note (rendering could depend on user preferences or CSS)
Similar to red links, unsourced claims could be (faintly) highlighted in the rendered page, as an encouragement to add citations.
The reason I am not moving this forward more quickly is that I would like it to be properly integrated into the MediaWiki 2.0 framework. In particular, the [[Source:Xyz]] should really refer to a Wikidata structure, so we can start managing our collection of references properly, for the benefit of easy and consistent citation throughout Wikimedia. The PRML will also allow more complex statements, as not everything can be atomized like the above examples.
Regards,
Erik