The best evidence that something could happen is that it did happen. Once you demonstrate that, all the pedantic nitpicking in the world doesn't change that fact. The timeframe for Oswald to move from point A to point B can't be known with certainty. That endless pedantic debate is to enter the realm of the CTer. All of that is no longer relevant if the evidence places him at the scene of the Tippit murder. And that is the situation in this case. The timeframe for Oswald's every movement is mooted if the evidence demonstrates that he was in fact at the scene of the Tippit shooting. And it does. Numerous witnesses place him there. So whether he walked, ran, got a ride or sprouted wings to get there, the fact remains that he was there. No one has to recreate his movements to prove that.