Are you saying that Chaney was faster than the trained agents who were alert to the possibility of an attempt...
How do you explain the fact that all of the spectators who are looking at the President don't have their heads turned as they would if the car was further down Elm street near the steps to the North pergola. Some of the spectators are facing nearly perpendicular to the street . They are standing on the sidewalk east of the Stemmons freeway sign ...and it seems to me that their heads should be rotated around to their right.
Notice the posture of the woman who is wearing a coat and a head scarf at the extreme left of the photo.... the car is nearly in front of her.....