When is it correct to use the form "I did want to ..." versus "I wanted to..." (substitute other verb for "want"). I often find myself changing from the former to the latter when I edit early drafts, but sometimes the former seems to better emphasize my "wanting".
EDIT: Part of my curiosity was that this has the feel of a slightly different tense, but it is not. The discussions in the following, which I found rather indirectly via the ELL meta site, are more what I was looking for. Difference between "did + verb" and just "verb+ed"