I find it hard to believe that Lee Harvey Oswald made those shots in that amount of time.
They had expert marksman, somewhat recently (last 10 years?), recreate it. These were guys that graded out higher marksman than Oswald did on his military rifle exam. Expert shooters. From first sound waves of the shots thru an open police motorcycle radio recording and film of the shooting, they could precisely tell position of the vehicle at each shot, and the time between them.
They shut down the street. Same type of vehicle. Used the same rifle, not the one he used but the same rifle. Very meticulous re-creation. They allowed the marksman to get acquainted with the rifle, they did not shoot cold.
They all had very poor accuracy and I believe only one time did someone even get off 3 shots in the allotted time, but did not make 2 hits.
What is interesting, there was a traffic light pole that consistently got in the way on the first shot, I think it was the first shot. They showed thru the scope what all this looked like. The first shot should have been the easiest, but everyone felt the first shot missed based on witness testimony. Many thought it was an engine backfire from a motorcycle. The pole is the same pole they had that day, at that time it was still in use.
They got a ladder and found an area that looked like a bullet hit it. They showed the pole, exactly where the cross hairs kept landing when that shot was fired and they found what looked like a bullet strike.
Now, those 3 casings very consistently fell exactly as they found them, and they have pictures of that. On one of the shots, one of the casings typically rolled all the way against the wall, probably the angle and the movement of the shooter and the boxes stacked around the shooter’s nest. And they found one against the wall that day. But it was pretty interesting to see that.
Their conclusion was no way one shooter landed 2 hits, and there had to be a 2nd shooter.