This door hanger/card punch issue reminds me of a nuclear story.
Years ago there was a research/training facility operating a Navy nuclear reactor, so the Naval Reactors inspectors would occasionally check safety & cleanliness. Comments made by the inspectors would be recorded and the company would have to write a letter to NR telling them what they were doing to fix the problem(s).
On one visit an inspector noted that the floor was dirty. Next letter to NR said that the company had cleaned the floor and added a floor-cleaning log to make sure that the floor was kept clean. Next visit the inspector noted that the log had hourly slots but that it had been more than an hour since the last log entry. Next letter said that the log was modified to emphasize hourly checks. Next visit the inspector noted that the hourly checks were occurring exactly every 60 minutes, which seemed unusually precise (e.g., falsified). The log policy was changed to require random visits every hour at intervals not to exceed 60 minutes. Next visit the inspector noted that log entries were still being missed. The log policy was changed to include supervisor initials next to each log entry. Next visit the inspector noted that some supervisor initials were missing.
It's easy to form the impression that the inspectors were a bunch of martinetic jerks, and unfortunately that reputation is not undeserved. However in this case the inspectors were only checking whether the company was doing what it said it was going to do-- they were only inspecting compliance, not the rules themselves. The more rules the company made for themselves, the more things the inspectors could check for compliance... and the more things they could find "wrong".
Which shows how far off track the company had gone from the original question: Was the floor clean?!?
As you've pointed out, Arif, if the pool is clean then it's pointless to argue whether or not the pool guy was there…