During the crash, if the market were functioning normally, people could have bought cheap ETH in the ETH-USD market and sold it at nearly the normal price via t

During the crash, if the market were functioning normally, people could have bought cheap ETH in the ETH-USD market and sold it at nearly the normal price via the ETH-USD and BTC-USD markets all without leaving GDAX. Their outage page has the grace to mention that there were slowdowns. A few seconds is normally long enough for liquidity to transfer between markets and this time it wasn't. That's the issue