Talk:The Pulled Groin Extrapolation/@comment-146.198.82.24-20150705191123

There is a big error in this episode, the HO train set that Sheldon is operating is hauled by a diesel locomotive, but he makes the "wooo-wooo" whistle noise associated with a steam locomotive. Someone with Sheldon's knowledge of railways and attention to detail would have known that the diesel has a horn and would have made the appropriate noise. A better gag would have been for Amy or Leonard to make the steam loco noise and for Sheldon to correct him or her