How to Check for Zener Voltage Regulation

How to Determine if a zener diode regulator circuit would actually provide voltage regulation at the stated zener diode voltage.
This video explains how to determine if a Zener diode regulator circuit will actually regulate.
Please note that in the video, mention is made of the load increasing from 200 ohm to 500 ohm. It should have been more correctly stated that: " The load resistance increased to 500 ohm." This means that the load actually decreased or became lighter.