I ask this sincerely and with no snark: why do you feel this needs to be a requirement? Would your life really change that much if that one road trip took a little longer? (And not for nothing, stopping like that made the trip feel faster than it ever had for me in the past. Breaks are good!)

Two competing things: A) I absolutely LOVE driving; it's my favorite leisure activity; and so whenever I get the chance to road- trip, I want to spend as much time driving as possible. B) Kids at Disney want to spend as much time there as possible, so minimizing drive days gives you more park days.