The other problem is there are cops with radar guns on the back roads. Good job, ticket tourists and put more people on I-4, but that's the way it goes.
So like the others said, just get up early, take Kirkman to I-4 at 07:00am, and follow the signs. The lines to get into a Disney park actually start around 08:00am. They let people in around 08:45am, everyone lines up at the rope, and then at 09:00am they walk to a thrill ride. The sooner you show up, the closer you are to the front of the rope.
The thing about the real world, is you'll forget something at the hotel and have to go back, or you'll miss a turn, or there will be traffic. So leaving early is always a good idea.