You know his long-term holds are guaranteed to be exposed to this kind of flogging from time to time. How does he manage volatility? Options?
By collaring his stocks or collaring an index that correlates well to his entire portfolio (like SPX).
I suspect (but don't know for a fact) that he buys with a classic value margin of safety and does not use leverage. Classic value layer don't believe they can call the market. With that kind of entry and his LT orientation, corrections are probably not something he would bother with, although he did hedge the USD exosure of his US companies.
They use options, collars, portfolio insurance on regular basis. They are always writing covered calls or selling puts to acquire stocks. This guy knows all the ropes and when they hit a market downturn he probably shorts the weaker stocks and gets his yah yah out. There is another trick you can do to safeguard your portfolio