The board is slow, so I'm going to throw something out.
I'm a planner as well....not to mention that my kids tend to plan things as well on days off of school with their friends.
"If you remove the sports/activities from the wohp time, the parent at home with the holidays/vacations/sick days and so forth....when then would the wohp find time?"
Why would they have to find time? They would have the same time off work that they would if they were doing sports events with their children. If the childrens sports/activities are done while they are at work then they can do other things with them when they are not at work.
First, let me state that I don't think "alone time" is some panacea or ultimate goal.
Is this supposed to be related to the parent not knowing when their spouse is going to work and when they're planning to hang out at home?