"Your focus should be on when your step is considered to have been taken or when your foot is planted (not when to start to move your foot to take the step which I think is why the desciption for when to lower is vague or not excruciatingly precise)"
The descriptions of rise and fall are relative to the official period of each step.
The officialy period of a step does not begin when the foot is planted! Instead, it begins when the moving foot passes the old standing foot, and ends when the other foot passes this new standing foor. Or for a closing step, when the foot is halfway closed.
If you aren't going to use those official defintiions, then you have to adjust the given rise and fall instructions to take into account the difference between the official definitions and the definitions in terms of which you do wish to speak.