Actually there is a point to this one. Though it fails significantly when you think about Fiendfyre. All anyone would need to do is cast Fiendfyre in the neighborhood and poof one dead Harry. Then again there is the point that there are no really tracking spells aside from Point Me. Unless Voldemort was staking out the place, he would have to wait for any Death Eater he tasked with following Harry to make a report on this movements. He also could have struck the Hogwarts express, but didn't. Still your idea is spot on, if the wards existed and were effective (not likely as Voldemort became a blood relative after GOF) running away would mean a death sentence, provided Voldemort found out.