Actually, I liked the episode as such very much. It's my favourite of the season, and if Hugh Laurie doesn't get an Emmy for it then they might as well abolish the award. But that doesn't alter the fact that there is some very sloppy organisation and writing going on in that show. They get by with it because they are a brilliant crew, but they 'can do better' and like Cuddy we have a right to that. They just need to impose a few rules and structures on themselves (yes, it's unpleasant and it usually causes more work, especially at the beginning), then they wouldn't make stupid little mistakes that annoy people no end. If I were paid for writing for that show, I'd be mortified if I were caught in a major factual mistake like the sister's name. Character continuity mistakes are obviously much harder to prove, but I nevertheless believe that we've been subjected to those, too. After all, if the writers can't keep track of their characters' names, are they likely to remember their likes and dislikes?