The Shift
Moving fielders to where a hitter usually hits it.
How it actually works. The current rule requires two infielders on each side of second base, both with their feet on the dirt when the pitch is released. That ended the three-infielders-on-one-side alignment that pull-heavy left-handed hitters faced constantly.
Why it is done, and when it is wrong. The shift was never new; teams shifted on Ted Williams in the 1940s. What was new was doing it on everyone, from spray charts. The restriction is one of the few times the sport has legislated against a strategy purely because of how it looked.
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