Using Diodes instead of a Relay
Logically, yes, but in your circuit with no relays, note the diodes are in series with the motor, so that 1) the motor will see 12V minus the diode's voltage drop (say half a volt), and 2) that voltage drop multiplied by the motor's current (2A is it?) will generate heat (say 1 watt) within the diode and 3) 1N-series diodes are only rated for about one amp (at cooler temps).