Until it turned out my Origin Live Conqueror did sound better just sitting in the hole
Yes, Einstein, thats what happens when you have a poorly designed arm with rattly bearings or poorly designed home brew TT that fails to deal with the cartridge vibrations that you talk about.
Atmasphere is absolutely correct - compromise loop rigidity between the cartridge arm platter and you cant measure the groove accurately.
If you are having probems with that then get a better TT and arm.