Record clamps on LP12

Any experience using a record clamp on an LP12? I would ordinarily just try a couple and listen for the effect, but with this I am concerned that even if it sounds great, the added mass might be a long term problem for the bearing and perhaps for the suspension too.
I've tried a couple (Mitchell reflex clamp, the "Pig"). Don't bother...they killed the rythm and pace!
This killed the rhythm and pace? Nothing else was affected?