As a life long maintenance guy that works on complex industrial production equipment, I find this situation intriguing.

We would often schedule maintenance tasks for change over times when there would be a small window of opportunity to perform inspections and adjustments without any affect on production schedules. If an outside delay occurred in the change over process such as having to wait on materials or tooling, we would consider the additional available time as an opportunity to get the scheduled task done early and possibly do a better job or more thorough job than would have been possible with the original schedule.

If they are really trying to find threats, if the purpose of the gate check is to secure the aircraft, if they are there to search bags, they have an opportunity to apply this to more passengers in a more thorough way that is less likely to delay or irritate passengers than the process that waits until the last few precious moments before the flight leaves to initiate the process.

It becomes obvious that the purpose of these checks is not the threats to the aircraft but inflicting the maximum intimidation to the passengers by unnecessarily delaying the task to the time of maximum stress for the passenger.

If I had waited around drinking coffee and talking to my coworkers while squandering productive time, and then waited until the last minute to complete a task that should have already been done, I would have had to answer to boss in a way that I certainly would have sought to avoid in future situations.

A great truth of complex systems is this: The purpose of a system is what it does.

Do not believe the public pronouncements or the published information. Observe the system, watch and observe what it does. In that you will learn its purpose. We here are observers. It is the reason for much of our skepticism.