Record clamps: do they really make a difference.

I am of the came which says If you cannot hear any difference, then, for you, there IS no difference.
Do some task because someone else might hear it (but they aren't there with you) is crazy IMO.

I ony use a weight clamp, and that onky when a LP seems too slippery on the platter due to slight dishing.

Otherwise for me, a clamp is a PITA to bother with.
(I am really lazy)

I have a sota jewel. My friend with a sapphire brought his clamp over. Within 10 seconds I was in shock. It took the clarity to a whole other level. Are you putting the clamp on tightly? Is your table set up properly?

To complete the mating on the vinyl with the platter, add a heavy weight periphery clamp.

It all depends on the table. The worse the turntable, the greater the need.

It depends on the platter. The old VPI TNT platters we're recessed in the center with a washer around the spindle, so when the clamp was turned down the record was held flat across the entire surface. The result was the entire surface was part of the platter. Worked well if you did not "over tighten" the clamp, resulting in "dished" record.

Vacuum hold down also works in most cases.