There are no testimonies backed by evidence showing bombs existed. I did watch each video, though I skipped around some, I got the plot of them. Firefighters THOUGHT there might have been bombs. They never said it was bombs, they never found any bombs. They simply thought they could have existed. If bombs were found by firefighters, law enforcement officers, whoever, then it would be included as a fact that bombs existed. But no evidence of such bombs have ever been found.

And yes I watched the link, it still doesn't account for the size of the project, and the limited timespan workers had each day to plant them. You're also forgetting that bomb-sniffing dogs searched the building every day. If you're to suggest that every bomb was planted the night before the attack, and then noticed by no dog, no person the next day, and not one little mistake or sign was left behind, then you're truly delusional.

Of course covert ops exist, but something of this scale would be impossible to successfully go through with. No wires remained, no bombshells, shrapnel, fragments of the bombs, or any sign of explosions not caused by the planes were found. If even one sign of a bomb existed, the government would have its ass handed to it.