It is an interesting idea but backing out on a coaster that was already announced is an extremely rare occurrence. In all the years I've been in ACE, I can only think of three: Hersheypark's Turbulence, SF New England's Dark Knight wild mouse and the Zierer coaster at Six Flags Fiesta Texas. I don't even know if the last one was ever announced, it just appeared in the parking lot and on the park map, but was never built. With just those three, and the fact that there are no pictures, there's not really enough material to put together an article.
Thanks for the suggestion and if I am missing other coasters, please let me know. But as of now, I can't see this becoming an article.
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