I'm not surprised she returned to her old ways either - it seems like people are more prone to go to the extremes rather than practicing moderation. Part of why people try specific diet plans is that they provide rules and structure. It can be simpler to count calories, use a point system, or cut out certain foods entirely than to practice moderation and smart choices without strict guidelines.
On the other hand, I admire the SYC group's discipline! I'm no participating because I've been working on filling gaps, but I've been very conscious of my shopping since the start of SYC. I've bought one pair of booties, one pair of sandals, two pencil skirts, two cardigans, one long sleeved tee, one short sleeved tee, one tank top, one pair of skinny jeans, one pair of leggings, one pair of tights, and two dresses. Most of them fill gaps, all of them are being used frequently or will be used frequently once it gets colder, all of them fit perfectly, and ALL of them are in a neutral color (brown, cognac, black, denim) or are green (olive or army). This has taken work and self-discipline, as there have been many less versatile pieces, items that almost fit right, and bargains that I've decided not to buy.
I guess what I'm trying to say (sorry to ramble on) is that abstaining from shopping and conscientious/focused shopping both require work, foresight, and self-control. But the lessons and habits we learn from one don't always translate to the other.