I guess you dont remember 2008 financial crisis. Many stocks have had their NAV also cut in half.
Meanwhile people that bought 10 years ago collected $14.6 but lost only $7 on NAV. Thats 50% return over 1 years or 5% per year close to the S&P.
The author is wrong on ROC. CEFconnect shows only 4.3% annually. Beware this guy is totally wrong.