If that's the language they are using then it is a bit confusing. A machine can certainly be BOTH clutched and have a geared head.
On many machine tools, the spindle is started and stopped by starting and stopping the spindle drive motor. The motor can be connected to the spindle either by a belt, or through gears, or some combination, but when the spindle is stopped the motor is not running. This is the way the few Victors I've been around work, but I'm far from a Victor expert.
Many other machine tools, usually larger ones, have a clutch to engage the spindle. Again the drive system can be belt or gears, but the motor stays running, the clutch is just disengaged to stop the spindle.
This matters to the RPC because when the motor is started on a clutched machine, there is no load on the motor. The clutch is engaged only after the motor is running at full RPM. This requires less current than starting a motor with the added load of turning the spindle and driving members of the machine.