Look who's talking about overthinking. You're pathetic, Storing.
Yes, Mrs. Kennedy is slightly moving JFK as she leans forward to look at something, but in order for her to cause such a sudden movement of JFK's head as we see in the films, we would see her violently tug on his arm in order to cause the type of movement we are are seeing of the head. Your idea is absurd.
All you need to do is give an objective look at the Assassination Images. The neck wound caused JFK's Arm/Hand to clutch at his throat/chest level. Jackie, TUGGING DOWNWARD on this Arm/Hand would easily tilt JFK's head downward. This forward head movement is minimal. I understand the head movement that is required to support the LN

. It just ain't there. Never has been. And now there is the Knott Labs Laser 360 SCIENCE declaring the, "SBT IS IMPOSSIBLE". After 60 yrs, the LN

is all crashing down.