I umpired two years ago (ASA) and I don't have the new rule book, but back then you had to break the wrists on a swing for it to be considered a swing...
This is a false statement (either two years ago or today).
It sounds like you are confusing the often confused advice in the Rules Supplement about checked swings. Breaking the wrists is one of the guidelines offered to an umpire that he
might use to help him determine if the batter has offered at a pitch or not. It is NOT a requirement of the rules that defines a swing.
The ASA definition of a "Chopped Ball" is given under Rule 1. It is "when the batter strikes downward with a chopping motion of the bat".
The rule that covers this is 7-6-H, which states that the batter is out if he "bunts or chops the ball".
So what does a chopped ball look like? The above analogy about swinging downward, like chopping wood or swinging an axe, is a good one. Ultimatetly, whether or not a ball was "chopped" is at the discretion and judgment of the umpire. It can be kind of a grey area. As a rule of thumb, you have to decide if the batter swung more "downward" than "forward".
Actually, the umpire was more concerned about him swinging half speed than chopping down on the ball. He was chopping down on the ball, but cutting it over the infielders head.
Then he was probably concerned with something that he shouldn't be concerned about! The rules to not address or dictate the the speed with with the batter swings the bat. If these batted balls were landing past the infielders, it's probably safe to say they were neither bunted or chopped.