The game will fail to let him take the extra base at a higher than league average rate, simply because a PR baserunning rating will prohibit it. He would get thrown out far more times in the game than he did in real life with his PR rating. If DMB kept baserunning stats, I don't think a PR runner could accomplish close to 50% XBT no matter how aggressive you were with him, without getting nailed a disproportionate amount of times.