I agree that they've come to a false conclusion in that video, saying that the curve (arches) adds rigidity, because the scoop performed well in a rotation test.
The laws of physics explain it far better, specifically Rotational inertia.
Take two bats of the same mass, one with huge edges and less mass in the centre (a scoop for example), and an older traditional bat with smaller edges and more mass in the spine.
The one with the mass on the edges has more rotational inertia, so with the same ball impact on the edge, it will resist spinning in the hands more than the bat with more mass in the centre. That's why the scoop performed the best in that test - it's a scientific fact.
Think of an ice skater starting a pirouette with their arms extended, and when they hold their arms close to their chest the exact same ammount of force now spins them at twice the RPM. I know it's not a perfect example of what goes on in a cricket bat, but it's a demonstration of how the exact same mass has differing rotational inertia when mass distribution changes and nothing else.
The science backs up Mfarank's experience, that a bat with a bigger edge and more concaving will rotate less in the hand IF you hit the ball on the edge, however the difference would be slight.
Of course, if that was totally desirable, we'd all be using flat planks.
The flipside of the question, is "does the lack of a high spine detract from the shots that come from the middle?". If the popularity of the scoop was any indication, the answer is probably no.