What’s His ERA Against Lefties?

Not only can the new Windows 8 operating system allow you to split the screen with two programs, but it can provide splits for unsplittable statistics:

The YouTube commenters can fight all they want about Mac vs. PC, but I think the more serious issue here is that of ERA versus lefties. How does that work?! HOW DID WINDOWS BREAK THE CONTEXT-DEPENDENT CODE?! DO EARNED RUNS COUNT AGAINST A PITCHER ONLY IF THE PLAYER ON BASE IS A LEFTY? WHAT IF THE THE RUNNER IS A SWITCH HITTER?!

Windows knows.