Mechanical damping comes in many forms - in the Naim Aro that I have the location of the counterweight and the lowering of the centre of gravity to below the pivot point provides about 6db of mechanical damping to the stylus. Furthermore the bearing deisign - radiused tip sitting in a slightly larger radius cup provides another 2-3db of mechanical damping. Thus mechanical damping can be achieved without the use of chewing gum, blue tack, rubber bands, ky jelly and other addons if an arm is well designed.
Martin Colloms - Stereophile
Lowering the counterweight to about record level has given the ARO excellent stability. This also lowers the center of gravity to below the pivot point, providing about 6dB of mechanical damping of the stylus. Another 2dB or 3dB seem to come from the bearing cup, which has a sapphire insert. The bearing is the ARO's stroke of genius. In other unipivots, a sharp pin is mounted to the turntable and the arm carries a cup which sits atop the pivot point. The ARO's arm carries the sharp tip, resting this atop a stationary cup: a true mechanical ground, and the only spiked tonearm I know of!
From an engineering point of view a true self centering unipivot provides the most rigid bearing possible in a tonearm - no chattering, no sloppy bearings, no drag on maladjusted gimbal bearings. No jitter or dither !
In my system the Aro is more resolving than the Fidelity Research FR64S.
The Graham has an upside down bearing - cup is in the arm - is not a true mechanical ground in the context of Martin Colloms comments above. This coupled with excessive arm tube dampening was the reason I chose the Aro over the Graham several years ago..
As an aside the Hadcock is not a true unipivot - the spike sits in the crook of nested ball bearings with multiple points of contact. Similarly I believe that the Satin "unipivot" that Raul lauds uses a nested ball bearing system as well and I suspect is not a true unipivot.