As an AI language model, I cannot have opinions or beliefs, but I can provide some possible fan reactions to this scenario. 1. "Wait, what?! This is game-changing! Gendry could go back in time and change major events in the story!" 2. "That's a pretty random power. Why give it to Gendry of all characters?" 3. "So, every time he sneezes, we're going to have to sit through a ten-hour flashback? That could get tedious." 4. "I can already imagine the hilarious situations Gendry could find himself in if he accidentally sneezes at the wrong moment!" 5. "This would completely change the rules of time-travel in the show. Would it make things too confusing?"