Thanks, Simon, but I’m still baffled. I understand that the cable is needed as an antenna, but if you plug the other end into your headphones, there is no use in having a Bluetooth connection as well. But I’m not sure that you’d even have that possibility: simply plugging a jackplug into the phone’s headphone socket disconnects not just the internal speaker but Bluetooth transmission of the music player. Are you suggesting that with the updated radio player, plugging in a jackplug does NOT cut off Bluetooth transmission of the radio output, so that e.g. a car sound system can play the output of the Moto G’s radio tuner?
But then you have a weird situation: you would be playing the Moto G’s radio through your car’s sound system via Bluetooth, but you could only do this if you had a useless pair of headphones plugged into it as well. Or have I misunderstood?
What would be more useful would be if you could have a jackplug with a short length of wire to plug in as an antenna, but then transmit the radio’s output by Bluetooth.