Apparently it's not just time and history that evolves in the Assassin's Creed games, but the NPCs' artificial intelligence too, as YouTuber cchrist1000 sadly experienced during his ACIV session.
It might actually be impossible to sneak up on those guards without being caught. A glitch like this is truly the nightmare of any stealth game enthusiast.
Assassin's Creed IV's AI is impossible to sneak up on [YouTube]
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