Covertentry experts have employed this technique quite successfully in many venues around the world, and the exploit is fairly well known in our community.
In my earlier post, I rather sarcastically questioned whether Kaba engineers, in the 1960s, were aware of the concept of magnetism as it applies to covertentry.
As an example, last year at the Dubai Police Headquarters we taught forty criminal investigative agents about lock forensics and covertentry in an intensive hands-on setting.