GL_POINTS primitive with iOS OpenGL ES 2.0

I was having issues with GL_POINTS today where I could correctly render lines and triangles but not points. It was working fine on simulator but not on the device (not very uncommon it seems), but I was able to get points working again by changing gl_PointSize = 1.0 in the vertex shader. I’m not quite sure why this is happening and it seems like this shouldn’t be necessary, perhaps it is only a red herring…