I agree, I briefy considered this type of clause, in the end didnt do it and I am glad. And 2 hours is so short! That is just going to create massive problems. You are constantly going to have to be consulting each other. Do you really want to have to contact the other parent first if you want to go run errands and it takes 2 hours and 15 minutes, or 2.5 hours instead of just getting the teenager down the street as a babysitter? You would waste time just getting back and forth to each others houses that it wouldn't even be worth running errands kid free.
And then how do you define what is not compliant with your 2 hour rule? What if your kid is invited to a friends house and you go out and do something during that time. Is the other parent going to say that it should have been right of first refusal? What if your kid is playing at the neighbors house and you have to suddenly run out to get something andyour neighbor says, just leave him here, are you now not in compliance with your 2 hours rule? What if kid is at grandmas house for a sleep over on the weekend. Are you now breaking your rule and you should have given the other parent right of first refusal? What if you have to work an extra day and grandma what to take your child, are you breaking your rule?
Just each arrange your own babysitters on your own parenting time. It doesnt mean you cant ask the other parent to take the kid if you have a work committment or something. you still can, but you dont have to.