I just read the post where it said it was done off camera. But in that scene Walt is never off camera. So they're implying that he slipped it in there at some point by her stirring in the sugar packet, but it wasn't ever shown "how" he managed to slip it to her..at least I think that's kinda important if you're just going to come out and say later that "I slipped you the ricin that's why you feel very ill." IMO that was poorly done unless I'm just completely missing something and need to watch again on dvr.
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