Cool again as usual... I've been thinking about your post but for a different purpose. There was a lot of chatter on the Movado Sapphire in http://community.facer.io/t/can-someone-create-a-movado-saphire-face/7030. For sure, it's a simple face to reproduce but is it really that simple if you think more about it?
I make my own Hour/Mins/Secs hands but if the watch face is busy with a lot of graphics, I dont spend excess time on shadows. I'll make the basic shadow and leave it at that or just use the Creator's shadow. But on the Movado Sapphire, you really have to go the full 100% effort on the hands - they are the only element on the face!
At some times the left side of the pointer is lighted and the right side is in shadow.
But later in the day, the shadows flip sides as the shadow stays on the bottom.
I'm also not sure what happens at 6 and at 12, but wouldn't it cool if the shadows on the hands moved and changed as you tilted the watch with your equations above?
Just thinking out loud.