I would love to see the Daily Dish piece about it. I think that, like agave, we are all making our best guess. Someone did note that those yams aren't like ours so it might be a factor. I do think the agave thing makes sense because low glycemic or not (and it's still much higher than fruit we don't eat) it is fructose. Once again though that's just my opinion
We will always run into foods that Dr. A didn't put on the list. It's much easier to make those informed guesses about Phase 2 foods.
*and as Zeff said, ultimately we decide for ourselves. That should be done carefully, testing a little and watching for cravings.