Her main work over the last few months has been local radio in which I think silence can make stations fall of the air in which case she would have to speak constantly so she may have trained herself into that way of thinking.
The silence detectors are not that trigger happy, normally set to 20 or 30 seconds. There's nothing wrong with silent pauses on the radio, Wogan was a superb exponent of it, but yes local radio particularly has a culture of every microsecond having to have some sort of noise broadcast, regardless whether or not it's just random drivel
All true, but listeners are really unforgiving about silence on air. Pauses of between 2 and 5 seconds will cause some listeners to think the batteries in their radio have gone, or some other similar thought, and most if not all will think something like that after the five second mark, so silence of any kind in radio is not encouraged, unless it is for dramatic effect.