Useless swipe in App Exposé in Sierra
i think i know what you're talking about. expose used to have this really annoying "feature" where it required a mouse move before it would register a click. so if i used expose and the window i wanted was right under my mouse cursor, i couldn't just click it. i had to move my mouse a little, then i could click it

but, i just tried reproducing this in macos sierra and the problem is gone!