I had forgotten, that such a topic, like all other audio topics can have as many opinions as there are posters.
Should the moderators permit, this could probably be a thread that could numbers into the dozens of posts.
Most feel the benefit of a clamp to be resonance control. Even Harry W himself no doubt believed this was the sole benefit. But of course there are others.
I know many here work very hard to achieve proper set-up of Table-Arm-Cartridge, and we can talk about things like Overhang, Azimuth, Zenith Angle all day long.
To me, it doesn't make much logical sense after all this hard work, and now you're placing an LP that looks like a Taco, or becomes Taco'd after improper precise clamping of an LP to Platter. Not to mention th extra work a Stylus-Cantilever has to do following a warped LP, and the detriment to good sound because of it.
The beauty of a Screw Down Clamp with Tables that posess the VPIS design, is variance of Clamping Force is easily obtained. With a weight, there's no adjustablity. The screw Clamp can be just barely applied, or provide much more clamping force than any weight can apply.
If one seeks the additional Mass, then buy the heaviest weight available.
All VPI Platters have been specially designed to work hand in hand with a Clamp that adheres to VPI's Clamp Design.
The use of the Rubber Washer was cheap, but effective, and smart.
Why TT Weights chose to veer from the VPI Design, and not at least provide a comparably designed product is unknown to me? I'm sure they have the expertise to make a beautiful two-piece clamp with adherence to the VPI Design had they chosen to.
I know many will comment about the sonic improvements, or lack of, with different Clamp Designs. I'm as well concerned that the Clamp-weight does it's intended job, and prefer the limitless range of adjustability/clamping force that a screw type design has.
I feel it does little good to be looking at a gorgeous Clamp, yet the LP looks like a Frisbee while in play.
While the azimuth error variance may be small, I would assume it is still there.
I myself chose a custom machined Screw Type Clamp made by a local machinist, but it does precisely adhere to the VPI Design. Mark