If this happens, Berkshire will continue to chug along and outperform S&P upward too - and with 25% cash. From what I've seen it has kept up with SP and a little bit plus.
Spot on. Reading a lot of commentary, you'd almost miss the fact that through Jan 1 2019, BRK has outperformed the S&P by a hefty margin each of 1,2,3,4 and 5 year time frames all the time keeping solid firepower, a defensive approach and outstanding business results.