Just my opinion, but people for whatever reason are attracted to that corner shooting position where the E-W Picket Fence section meets the N-S Picket Fence section. People generally just stand a guy in that corner spot. Not only is that corner position highly visible, its' Line-Of-Sight (LOS) is horrible. That position has: (1) a tree to contend with, (2) the Alleged/Unknown 3 Guys standing at/below the Landing on The Steps, and (3) the Stemmons Sign if firing early-on. That corner position is roughly where Files claimed to be. An experienced Assassin such as Files is Not going to place himself in that shooting position. As an aside, I have always liked Files alleged "calling card". His claiming to bite down on the Bullet Shell and then placing that Shell atop the picket fence rail, has a flair to it that would immediately attract the attention of Dirty Harry Callahan.