Now that's, um, detail-oriented, aerteP! I can't swear I've ever gotten quite that fixated. But...
Very recently I played with the Celtic Knot thing in order to give myself some ideas about where my NaNoWriMo novel might go, and while I did get some insight into character dynamics from it, I also got a little distracted making curly shapes with Adobe Illustrator. Also got stuck a little trying too hard to adhere to what the artwork was doing. The trick, I think, is to abandon a tool once it has served its purpose (cf. Buddhist anecdote about carrying rafts around). My attention got refocused on how the characters' actions affect the goals of other characters, which was good. But sticking with it too long, I risked getting obsessed with "No! Blue line goes over green line, so I have to have another scene in which..." which was bad.
The best specific example of structure saving my butt that I can remember is a story I was writing on deadline (college assignment) that just wasn't coming out. My premise was not turning into a story. Once I made the decision that I'd have one scene per day of week, suddenly not only was deciding what happened in those scenes easier, but I had some extra thematic weight materialize along the way to do with Good Friday and Easter Sunday and Going Back To Work On Monday. So.
The story I'm working on now has a structure already, a sort of fairy tale 3-repetitions/variations-of-basic-action thing, and I think it's been bogged down in my head by Too Many Ideas. I've set it in my home neighborhood, full of setting details and childhood memories to pillage, and I've got about three different directions the "how does it work" of the what-if can go. I think outlining it on paper will help me better define the story and so cull out the ideas, memories, and details that don't serve it.