In the basic embodiment, the transmission includes (a) a minimal-orbiter gear complex having only a control gear and an output gear interconnected by the gearing portions of at least one cluster gear supported by an orbiting web responsive to an input drive provided by a primary engine and (b) a single, infinitely-variable rotary control device providing resistance torque to counter engine torque to slow and stop the control gear of the orbital complex. The rotary control device, which may be a hydraulic jack or an electrically braked magnetic wheel, provides no propelling motion but rather only provides a resistive torque. In a preferred embodiment for automotive use, the engine torque is split at all times between two mechanical paths. One path drives the web of a minimal orbiter gear set, and the other drives the sun gear of a single, standard planetary gear set.