Dennis,
Now and then it happens to me also. What I thought I have learned is that it is 'always' caused by me overdrawing slightly - even a 1/4" will do it. I learned something very important from watching your video that is going to help me too and will modify my statement.
As Arne said, your form, line up, etc. look good prior to your release - then, at the time of release your head turns toward the string and I think that might be caused by connecting your head/neck muscles with the rearward tension on your shoulder. Try isolating your shoulder and only pull with the back and don't allow your head to pull around to the side.
When it happens to me it is always at the start of a shooting session and after I loosen up it stops (before the bleeding becomes excessive) :rolleyes:
Good Luck