Update 12/18/23: An alert viewer let me know that the segment beginning around 07:00 is not quite correct. The condenser does discharge back into the circuit, but this discharge has no effect on the spark intensity. It occurs after the spark ends. The capacitance of the condenser has only a minor effect on the spark intensity. As long as the capacitance is above a certain threshold (likely .22 mfd for Model A) and the condenser is in good condition, it is safe to use.

Once again, sadly, there are no Model As in this video, but there is a bunch of basic electricity physics! In this video, we:
describe what condensers are
show how Model A and Model B condensers work in the ignition system
dissect a condenser
show three ways to test condensers for proper function

Thanks again to ‪@ModelA‬ for the technical assistance. I am not formally STEM-trained, so if I got any of the concepts wrong, please let me know in the comments.