I didn't say you HAD to make the attempt, I said you'd rarely get the call if you don't. I think this particular scenerio is a bit of a gray area. I think this may just be one of those "had to see it" calls. What I meant was that I'd be slow to call obstruction on a play where the runner wasn't really obstructed from doing what she appeared to be determined to do anyway prior to the fielder's act.You don't need to make an "attempt to advance." You can be obstructed on an attempt to retreat. Refusing to call obstruction when she's going back to third makes no sense. What if they tag her out?