IF your sweet spot ran from the handle to the tip....this demonstration would have merit.
But it doesn't. So it doesn't.
The demonstration shows a hitter with a merry go round swing path.....matching it to the path of the ball. It shows this....

Barrel is on plane. OK. But what if the ball is inside...or outside....of the sweet spot of your barrel....while it is 'on plane'? If it is, the adjustment you must make will slow you bat speed and reduce your swing quickness.
Great hitters do something else. Great hitters beat the ball to a spot. He must get the barrel to a spot when the ball gets there. He does not have the time to get 'on plane'....'a mostly horizontal plane'....by matching the rotational plane of the shoulders to the path of the pitch.....then swinging with the merry go round path around the spine. The sweet spot of the barrel in a merry go round bat path....that is 'on plane'....still may not square the ball.
Getting on plane is sold as THE ANSWER....yet....it can not be the cure all because of the 3 dimensions that pitchers use to get you out. In/out, up/down, long and short. The shoulder rotation plane, set to the pitch path, is one dimensional....and adjusting to the other dimensions degrades the swing. If you need to raise for ball height, how do you do it? If you have to pull in for an inside pitch how do you do it? If you have to let out for an outside pitch how do you do it? When your shoulders set the plane....you MAY....and I say MAY....have help with the long and short. But the shoulder rotation path ALWAYS struggels with the in/out and up/down.
The on plane barrel of a merry go round swing aligns with the path of the ball....then leaves the path of the ball....then reenters the path of the ball...ALL WHILE BEING ON PLANE. The ARC of the path causes that. Without a linear movement of the arms....you can not square bat and ball. And that linear arm adjustment is a swing killer. You have to POWER the adjustment with the arms....and that is classic disconnection from the rotation source. To make the on plane barrel align with the ball that may be inside or outside of the sweet spot, still takes another adjustment.....and that is an adjustment that slows and degrades the swing speed and quickness.
To reach your potential you must swing 'about the hands'. The barrel mus PIVOT ABOUT THE HANDS. The hands have to be the axis of the barrel's rotation. THAT axis adjusts in 3 dimensions quite easily without degrading the speed of the barrel or the power of the swing.

From his handset, Howard will PIVOT THE BARREL ABOUT THE HANDS....to the predicted spot for the collision with the ball. Since the barrel is pivoting about the hands...he simply swivels in the direction that takes him to the spot. And since the barrel is pivoted into an arc...and arc with great speed....any adjustment needed to square sweet spot and ball does not degrade his swing speed nor quickness. He simply 'pulls in' the already launched barrel....or 'lets out' the already launched barrel....the barrel that is pivoting about his hands....as needed to square bat and ball.
The 'get on plane' logic....widely accepted....is pure hogwash because it is taught with a merry go round 'around the shoulders' swing plane. Great hitters do not have that swing plane. Great hitters 'turn the barrel' about the hands to a predicted spot....and that turning of the barrel....about the hands....TO A SPOT....has a forgiveness factor because of the arc of the barrel....and the hands ability to adjust the direction of the pivot on the fly.
At high levels there is no time for that. The swing is launched then directed on the fly.
The barrel is turned rearward creating speed. Then, as needed, the hand pivot point can pivot to align barrel and ball.
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This is how to 'launch then direct'....and....be able to pivot the already speeding barrel to the ball....
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Merry go round versus pinwheel.