Interesting article. Why I am not expecting the market to plunge, it is wise to keep it in mind. Statistically, it is unlikely to occur, but statistics only define the most likely events to happen, not actual reality.
No one knows when these events are going to occur. They often happen when a scare takes hold with the general market, similar to someone yelling fire in theater. Next thing, the herd is clamoring for the door.
The key is to be mentally prepared for the possibility because it can be grueling, not if, but when it happens. Do you have a plan? Did you do a what-if analysis on portfolio price changes? Do you have a margin of safety? These are smart questions to have answered before the fact.
Be safe, be smart, be prepared, be well read and be successful!