[Of course, the other thing is well-documented: the sound of the chimes at 2.30p.m. on the tape. It breaks Hanlon's alibi but nothing else. Columbo's reinactment of the crime also just happens to compliment the chiming of the clock in Hanlon's office at exactly 2.30!!! This makes the script look a little contrived and artificial.]

You made some excellent points about this episode, but I disagree that Columbo's reinactment at 2:30 seems contrived. Columbo deliberately planned to be in the booth at that time in order to drive home the proof that Hanlon's alibi was toast.

Yes, the timing was "contrived," if you want to call it that, but contrived by Columbo.