Once you reach physical maturity, your speed starts to decline. That's not true for everyone, but it's true in general. Last November, Jesus Montero turned 23 years old, and he's a professional athlete at the highest level in the world. In a cup of coffee with the Yankees in 2011, Montero hit zero triples, and stole zero bases. Over a full season with the Mariners in 2012, Montero hit zero triples, and stole zero bases. Just three times out of 25 has Montero advanced from first to third on a single. Montero, statistically, has been one of baseball's very worst baserunners, because Montero has been woefully slow. This despite being so young of age. We've laughed about Montero spending the offseason "learning how to run". People should know how to run just from having been born and growing up. Nobody ever taught me how to run -- I just ran because I knew how to run, because I knew how to walk faster. I told my body "go faster" and my body responded and that was the end of that. As laughable as the situation was, though, Montero wasn't just slow; he had miserable, inexplicably stiff, upright form. Somehow, Montero didn't how how to run, and so there was promise that, with instruction, he could get a tiny bit faster. Running was a sad problem for Montero to have, but problems get addressed. The Mariners and Montero identified something that Montero could do better.