Never heard of people using LED lights in the morning. He's already supplementing with vitamin D, so what is the benefit of using the light on top of that?
The significance is on blue light. The same way it has negative side effects at night (which is why tools like f.lux and night shift exist), it has positive effects in the morning. Folks who live in northern regions struggle in the winter with depression due to the lack of sun and the impact that has on your circadian rhythm. Not sure the folks in SF have much to worry about here ;)
