I can tell that the author of this article looked at certain pictures and made some erroneous assumptions.
For instance, the ‘bag’ by the mailbox was not black. It wasn’t the ‘bomb’. But it was ‘circled’ in red on 4CHAN, so I guess the easily fooled got fooled.
Also there’s a picture of ‘white hat’ and ‘blue suit’ walking away from bomb point #1 towards bomb point #2 and he does not have the back pack on! What kind of a ‘spectator’ puts his backpack down and walks away in that kind of a crowd?