A high level swing can't really do what it's supposed to against a wheeled machine throwing hard. Nothing to time off of. Have to truncate your motion. If you have this kind of swing Photo 10 of 16, Fastpitch you are going to have to do everything before heel plant before the ball spits out. Timing off of an artificial arm circle is iffy. I agree with the need to get quicker which is what moving closer to the machine is forcing and I REALLY like the backing off portion of your drill forcing them to learn to wait for the slower pitch without starting their motion early but you won't develop the kind of swing you see in the above clip in close to a machine. Perhaps that's one reason we see the defensive swing mechanics so common in fp? With the shortage of quality bp pitchers the machine gets used more than for boys and the girls end up truncating the motion (getting rid of everything you see in the above clip before toe touch or heel plant). It's a problem. If you have a dad who is a former or current men's pitcher who can cruise all day long at a speed that slightly challenges your hitters, that's huge. And of course moving the machine close doesn't really get it done in terms of learning to track and time high speed pitching. It does challenge quickness but in an artificial way as I explained. Closing speed has been discussed many times. The timing challenge for a ball moving 90 is greater than for a ball moving 60 released from closer even though the reaction time is the same. Reason being the ball is in the contact zone for less time. Has everyone read the cannon ball analogy? Back off a cannon far enough the reaction time is the same few tenths of a second as it fires the ball over the plate at 200mph. Compare that to the same reaction on a 30 mph pitch from closer giving you the same few tenths of a second reaction time. Obviously the faster closing speed creates tracking problems and timing challenges well beyond the reaction time. So you really can't train for high speed pitching by moving closer to a machine throwing slower. But I DO love your drill. For me, it's about training to deal with the off speed more than training to deal with faster pitchers.