Michell clamp too tight for Spacedeck?

Not to highjack this thread, but I am wondering: Why would anyone use clamp?
I read that audiophiles experiment with different mats in hopes of decoupling a record form the platter and dampening the resonance/ vibration in the record.
Would not any clamp provide tighter contact between LP-Mat-Platter thus increasing a chance of resonance?
I might be wrong here but the tighter/stiffer the structure the better sound travels throughout...