I wish I knew. I saved it from a thread like this.
Air tight One Piece pacing and stunningly detailed animation.
Most of the cuts are good animation though. Some of it is too flashy and exaggerated for the sake of it, but generally there's nothing wrong with the animation at all.
That shot was from a really well-animated sequence by a top animator. It looks funny in a screenshot, but it's squash and stretch at work.