[ChuckMcM]

Well if you've used one of their airblade systems you can see that they have a 'down shoot' sort of effect. I've never seen an air-tap so I don't know if they achieve the same result but I suspect that the water uses the same path as the air, and so blowing toward the sink would make the most sense. In that case a poor basin design could get you into trouble with water bouncing back I suppose.