Researchers from Delft University of Technology have found high levels of historical accuracy in den Doolaard's descriptions of the events that took place, the methods used to close the dikes and the key people involved.

The bombings created major gaps in the dikes at four primary locations, breaching the coastal defences against The North Sea and allowing seawater to flow unchecked into inhabited areas of land.

[7] Difficulties in commencing the rehabilitation works included the fact that many dredgers were still located in areas of the occupied Netherlands, and around 25% of the Dutch dredging fleet had been confiscated and transported to Germany.

[16] The chapter title refers to the character Berend Bonkelaar's use of the term to express his incredulity at a particular method put forward for carrying out the dike repair works by an officer of Supreme Headquarters Allied Expeditionary Force.

The characters included den Doolard's depiction of protagonists such as the distinguished civil engineer and professor, Pieter Philippus Jansen[20] (represented by the character Van Hummel), many senior Rijkswaterstaat officials, the charismatic dredging boss Berend Bonkelaar (den Doolaard's pseudonym for J.J. 'Kobus' Kalis,[21] a founding director of the Boskalis company),[22] and Klaas Otterkop, the pseudonym of fascine mattress construction foreman Gerrit Visser of Gebroeders Van Oord, who supervised the installation of 36 fascine mattresses over a total area of 52,700 square metres during the work.

In the novel, they sign a contract to provide a bucket dredger early in the works, which van Hummel laments is subsequently delayed for lack of a tugboat.

In the English translations of the novel, he is referred to as the "mathematician from The Hague, a doctor of science" whose calculations help support the decision on the order of dike closures.