I think the Illusionists have been using this particular trick a long time.
Here the caption reads:
December 7, 1941: A small boat rescues a USS West Virginia crew member from the water after the Japanese bombing of Pearl Harbor, Hawaii. (AP Photo)
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What betrays the fakery in WTC scenes is the coinciding manifestation of shapes in the frame which are recognizably similar, much like how a human face is still recognizable even if the same individual face is shown fatter or thinner, smaller or larger, or more or less distinct.
It also appears that the technique involves, to some extent, taking a cue[s] from the frame terrain and then exploiting it elsewhere. However, it becomes tedious to attempt to designate point-to-point correlations since the components of the terrain cue are loosed from adhering to each other as they had related in the original and are given their own layers, so to speak. It's as if the components of the initiating image cue are transferred to the skin of a soap bubble where they have greater freedom of movement and can slide over and overlap one another. Compounding this, one transferred set of cue components may overlap another set.
To illustrate the concept I here hastily indicated a few component sets. The small shape in the corner would be the initiating terrain cue and the others varied expressions of the same.

An effort at some basic clone designations:

The sailor in white is discernable above, as are the other 2 men.

Below, the green box shows the terrain cue from the ship is expressed without much change in the smoke above.


As for who did Pearl Harbor? I have reason to suspect Japanese Al Qaeda:

