At the end of my review I said it was unlikely that the story released by the FSB report was true given the Russian secrete service´s history, successor of the famous Soviet KGB and from which Vladimir Putin himself emerged. But this conclusion was generic because I know too little about this body, which acts, as it´s name says, behind the scenes and is often object of discussion among analysts who have difficulty in mesuring it´s real power in Russia today.
Shekovtsov says the attempted terrorist attack was a psychological operation (psyop) created by the FSB in the "Crimea situation" context whose goal was to increase pressure on Ukraine and Western countries that imposed economic sanctions against Russia. He explains that this situation has paralell with Trust Operation of the 1920s created by the Soviet secret service. At the time, OGPU (future KGB) created a false monarchist and anti-communist group to lure real militantes of these causes. As a result, the militants were gathered, identified and eliminated by the regime, as well dissolved their contacts network in the country and abroad.
Chronologically this operation makes sense when we consider that before the arrest of the alleged terrorists in the night of 7 to 8 August, on 6 there already had great movement of Russian convoys in the city of Kerch toward the Crimea. A war on the battlefield always comes accompained by a propaganda war which makes it more predictable understanding of the strategy, but when the secret service comes into play the problem´s calculation gets more complicated. Otherwise the secret service wouldn´t be "secret". It is there to create confusion, confuse the enemy and set the trap to the real fighters, such as the Ukranian nationalist militants who where presented as the real makers of terrorism while the war´s trap was planned in Russia´s offices.