They're not showing the outdoor demo video, with how much operator effort is being used to compact the clay type soil.
My guess is, this device will give you a real YOGA workout. Same as my tamper bar with a 100mm compaction head, and my effort is lifting it up, and accelerating faster then gravity to the ground, with no spring to recover all that lost work. This may be better, but age of me, limits procuring another estate auction item for sale.