My current understanding of how game animation works is the animator will mark specific key frames (in an animation package) of an animation at specific times that mark specific poses of the animation to be played. So at .5s, since animation start, a certain pose of the animation should be displayed. During runtime, as the animation is playing, if the games framerate is off a bit and it asks to display the animation at .6s then typically the engine will interpolate the animation from the key frame pose at .5s and the next key frame pose, say at .7s, to display an in-between frame.
If this understanding is correct then wouldn't this mean your exact key frame pose would be missed and not displayed? So if the animation was a punch animation then that means the height of the punch's impact which was on a key pose would be missed? Does this mean it's good to extend and accentuate animations for a certain amount of frames if they are frames important for things like collision detection?