Philosophy: Bearing vs. Unipivot

I was looking at the VIV Rigid Float arm on AG today, and a couple of things struck me. Obviously, the primary one is that there is no arm offset on this arm, no overhang, no need for anti-skate. But, secondarily, I can really follow Ivor Tiefenbrun's thoughts on the Linn turntable: any relative motion between the stylus and the groove harms the sound. Stable bearings, whether gimballed or not, solve this situation. But there are so many unipivot arms out that are well-thought-out and well-regarded, including the aforementioned VIV.that there must be something more going on with them than there used to be, because there just HAS to be more relative movement with a unipivot arm than one with bearings. Someone please educate/enlighten me...