For what it's worth: I've answered my own question about event delegation based drag and drop. It seems to work quite well on my machine, which is quite a bit beefier than my old machine. I should try it out on there soon. But, I'll hopefully be releasing it soon in the form of a mostly-rewritten XoxoOutliner that will feature drag and drop outline items as well as keyboard navigation/control and in-place editing. And, it should actually start to become useful, since I plan to also whip up a PHP-based server side bit that will handle loading and saving outlines, as well as possibly a client-side bit that can save outlines using local browser storage. I have the technology - we'll see how far my ambitious plans take me during this hobbling sprint of development.