The article highlights the absolute exposure to the markets that the simple retail trader risks. When an event like this occurs, traders can be left owing more funds than they had available in their accounts, some lose $1000's... some lose even more.
A Stop Loss won't save you in a situation like this, nor will any open or close point on an oscillating indicator.
My Bots have equity protection logic built in, so if at any time the position generates 0.7 - 2% drawdown the logic kicks in and gradually reduces the position maintaining the predetermined risk level. But even this will not save against the situation detailed above...
Zero balance account protection (offered by some brokers) is really the only way to minimise losses as long as you have enough margin to comfortably cover your lot sizes in your trading account. A daily/weekly withdrawal regime can be used to keep your account at a predetermined level. So if a situation like the unpegging of the Swiss Franc transpired again, the traders only exposure is their account balance.