Which means DOUBLE THE PROFITABILITY!
This is simply not true. This would only be true if your MMQ used up 33% of its earnings in power usage, and the Single used up 66% of its earnings in power usage. In reality, these numbers are only 4.5%, and 9%. That is still technically half the operating costs, but it's not twice the profit.
I think he meant when difficulty catches up; ie, miners are back to operating at barely a profit.