I don't think it matters if it's unrealistic to sprint across a desert biome. Oblivion's mechanics are, and have always been, superior to Skyrim. Oblivion and Morrowind embraced the idea that you start out as "a dude"(tm) and end up a literal god like being. In Skyrim to do that you have to cheese the game. ES6 should try to do everything they can to recapture that magic, while improving upon Skryim's superior environment, atmosphere, animations, dialogue, and quest quality/complexity. If you could make characters more radiant than Oblivion that would end up the perfect RPG game generally.