Interesting reading up on possible links between ADD and OCD. I never would have considered it. I wouldn't classify myself as ocd- I certainly don't have rituals like washing or checking, and Lord knows i am not a neat freak.
Also the underlying thought patterns seem to be different, but I can say with certainty that portions of my day/week etc are very carefully inscribed into my mind out of fear of forgetting, or fear of -insert ADD characteristic-.
When I am forced to shift gears or re-write the plan, especially on the fly, I really fight panic. I become fearful (terrified actually) of dropping the ball or letting something slip.