Thanks for the excellent feedback to my post!
I can understand the benefit of working continuously on "Project A" when I'm in the right place, such as at home or in the office where there is a phone, laptop, and coworkers around me. But I can also see the benefit of just returning phone calls from all projects at once, because I'm in the car, on a train, I'm picking up the kids etc. and all I have is a phone.
Is the solution to list all my NAs in TWO contexts -- one for @Phone or @Laptop, and another under Project A, Project B, etc.?
Steve Pavlina wrote a good post that may interest others: