There was nothing worse than accidentally exiting a game on a Windows Phone by hitting the search capacitive button. This turned gameplay into a terrible experience, especially if the game didn't pause and issues arose. It also made it difficult for players to hop back into the gaming seat and pick off where he (or she) left off. This has changed in Windows Phone 8.1.
If you're enjoying a super-addictive play through of Rayman Fiesta Run, or are battling hard through Halo: Spartan Assault, Cortana (or search in general) won't load up should you hit the search button. If you do happen to want to access the search functionality in Windows Phone 8.1, simply double-tap the search key and you're good to go.
Related: Try accidentally pulling down the Action Center and you'll see what Microsoft calls the 'handlebar'. Same concept, you will need to do a double swipe if you're in a game or other 'full screen experience' app.
It's a small tip, but a helpful one nonetheless. Now get gaming in peace, people!