This document provides a critique of the book "The Templar's Secret Island" which claims the Knights Templar constructed churches on Bornholm Island arranged in a secret geometric pattern. The critic, an engineer, has several concerns: 1) Lack of evidence Templars were ever on the island. 2) Errors in the book's use of measurement units and map projections. 3) Geometric patterns in the book could be used to "prove" false hypotheses. The critic demonstrates constructing patterns to "prove" nonsense, questioning the book's conclusions. Overall, the critic finds significant flaws and doubts the book's central claims.