Using 2 x landing lights and alternating them could be a more elegant way of doing this.
And that facility is offered by the device under discussion. At rates of 44 or 88 or 120 times per minute.
Do deer have good hearing ?
Better than mankind, I should think - not hindered by any factual knowledge. Generally, human senses seem to be not the strongest in nature. But I also feel the beasts would soon get used to the sound. Wasn't the traditional way of doing it to always make a low pass, than a circuit, perhaps repeat, and only then to land?