Are we being trolled? I feel like we're being trolled.
I mean, it works? But I can't imagine how shaky the footage would be. The editing in the video seems to cover up most of the shot. Maybe the image stabilization in the phone can compensate? I would just hold the phone with my hands and shift my body from right-to-left rather than stick it to a pizza cutter WITH RUBBER BANDS.
However, that being said, maybe this could be an option if you wanted to get a shot of a pizza cutter slicing pizza from that angle? Still probably wouldn't be useable footage.