Okay, I left out the part about the editor -- or if not the editor, at least some utility -- being smart enough to let you walk-for and dump a chronological list of annotations instead of just doing the floating-sticky-note bullshit.

Annotations/'Wow-notes' without anchors in the current version of the text would be preserved and listed with broken or missing links, instead of lost forever when the associated paragraph object or whatever the hell is deleted.