Even on regulated markets it's very common to find people explaining their loses on manipulation from whales or inside informers, without any evidence.
The responsibility is never ours, there is always an obscure reason to explain our debacles.
Flash clash has to be caused by whale, since they are the only group that hold that many bitcoins and can dump that much on the market.
It was caused by there being less amounts of credit available on the exchange for people to borrow money to buy bitcoin on margin. When the first people were forced to sell, this caused the prices to drop, which caused others to have to sell because of margin calls, and the effect cascaded. This is why the price was generally lower on exchanges that offered margin.
