I really appreciate the post but I see mission and vision in a different way.
From my point of view, vision is a broader concept, it is how the company see the evolution of their market in the future, while mission is the role they want to play in that context.
For example, the vision of Microsoft was “a computer in every desk” when IBM thought that only big companies would have needed a computer.
Accordingly the mission of Microsoft became creating the software that could fit in these computers and ease the transition from big apparate to small pc.
Don’t you agree?