There it is easy for the car manufacturers to equip the heating phase with IR emitters and to arrange the retaining phase with warm air.
Thus it saves place and energy.
Predivide both methods:
Heat with radiation in few minutes
Following vergleichmaessigung of the temperatures by means of warm air also into the most remote corners inside.
Also here all possible variants are naturally established: In order to simplify the cleaning, the IR emitters can be covered with infrared-permeable disks. Energy is saved, if the emitter achievements run along like a run light with the vehicle.
Substantial time savings
Thus lowered energy costs