Perhaps it is the 911 Commission's report which is "grassy knoll". That report is certainly an attempt to co-opt the history books.
So much of what the commission did is tied to the 2004 election. Bush was right in wanting to wait until AFTER the election to investigate. Although there still could have been a whitewash.
One Plane, One Terrorist.
Plane Slams into Tower-1, ricochets to Tower-2, clips The Pentagon before crashing into an open field.