I think by Turn Coat LC was toast in terms of a current plot device.
Yeah, but I've always found it odd that Harry doesn't even think of using it to try to locate Thomas. It's alluded to, but never explained.
I don't think it would have worked anyway because the skinwalker could prevent it from doing so, but why is it not even mentioned? Harry's half out of his mind trying to track down Thomas, but doesn't use the one thing that's designed to find sh*t in Chicago?
Jim didn't have to use it. But it feels like too much of a deliberate choice to avoid mentioning it altogether. As far as I can recall, "Little Chicago" never appears in the book once.
....Just checked the EPUB file. No references to "model" regarding LC, nor Little Chicago itself. The only mention of it in TC is chapter 29, page 215 on Nook:
"A long table in the middle of the room was currently covered by a canvas tarp, and the floor at the far end of the lab had a perfect circle of pure copper embedded in it."
I dunno about anyone else, but that's always felt off to me, especially after all the effort Harry put into building and maintaining it. It appears, finished, in Proven Guilty, White Night, and Small Favor and is completely avoided in the narrative after that? Even JK Rowling—She of the Convenient Excuses—added a line about Time Turners being inaccessible in book six or seven.
From either a Doylist or Watsonian perspective, the above quote is significant to the narrative because LC is still there, but for some undisclosed reason, Harry doesn't consider using it.