All roads isn't all cannon. Horses were not cannon to New Vegas even though Chance's story depicts them. I think the excuse that was used to allow them, is that Chance is too strung out on Chems and was semi delusional.
Check out my Fallout Alaska Fan Lore Master Thread 2, pop in, leave a suggestion, or simply comment. Why is it called a Master Thread? Well because it's where all my updates will go first.
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Updated regularly. It's about Alaska and the Wackiness that ensues therein.