A couple of stats to ponder, from VE and Panasonics.

SP-10/2, platter 2.9kg, motor torque 6kg/cm.

SL-12xx, platter 1.7kg, motor torque 1.5kg/cm.

The SP-10/3 has a 10kg platter but they upped the motor torque to 16kg/cm to cope, obviously a couple of raw figures don't even begin to tell the story but I can't help thinking that the Technics designers probably had good reasons for doing things the way they did.