This is the episode in which Julia says that Willie has been delivered to a home for the criminally insane. If he had gone to Windcliff, she would have said so.
Well, chances are the original intent wasn't that Willie had gone to Windcliff. At this point Julia was still slated to be killed off, as was Barn (at least to Frid's way of thinking), so there probably wouldn't have been much point in ever bringing Willie back in the future. But, thankfully, Julia and Barn hung around. And when it came time to bring Willie back, the plot required a convenient way to do it, so, voila, Willie had been sent to Windcliff, where Julia could easily get him released - and knowing DC, the audience wasn't even supposed to remember anything about Willie having supposedly gone to a home for the criminally insane.
(Though one does suppose that Windcliff might have had a section for the criminally insane. I mean, they seemed to treat EVERYTHING there!
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