I visited Dealey Plaza in 1993, and one thing that impressed me was how
much Elm Street slopes downward as it starts to pass underneath the
railroad overpass. You don't see the full extent of the downward slope on
film, because of the two-dimensional nature of movies/photographs, but
most importantly because the people holding the cameras were standing on
the slope and were therefore slanting in the same direction.
Not that this bit of trivia proves that Oswald was the lone assassin, but
it provides some perspective on such questions as the angle required to
support the SBT.
