OK, I'lll admit that I made a mistake once but only once
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I was a fairly new baggage handler installing the chocks on a 737-200 that had just shut down at the terminal. There was an upslope at the terminal that while not visible, was definitely there(probably similar to the video). The result woud often be that after the park brake was released, the aircraft would move aft slightly only to be stopped by the aft chock. In those days, only one set of chocks were used on the right main gear where i worked. Because of this, the aft chock could then become very difficult to remove. One thing that could help was to use a longer chock(or install a shorter chock) in such a way with a certain percentage of it extending past the outboard edge of the wheel so that another chock could be used to bang out the chock installed behind the wheel when the time came for its removal.
In my case, it was a snowy day and there had been de-icing at the gate resulting in a fair amount of slush on the ramp. When I installed the chock after the aircraft shut down, I just placed the aft one in behind the gear as I had been doing in the past. When the brakes were released, the aircraft started moving aft and because of the slipperiness of the ramp, instead of the chock stopping the aircraft as it normally would, the aircraft started pushing the chock aft along the slippery surface. A coworker ran past me(I was unaware of a problem yet) and jammed his foot onto the back of said chock which then had enough ground contact to stop further aft movement. The airplane moved aft about five feet. After that, I always forcefully put the aft chock in followed by a good kick to ensure that it was securely jammed behind the wheel and able to hold the aircraft.
The good old days.