I think the reasoning behind his math:

Bitfuty Power / Antminer Power = Bitfury is drawing 4.615 times more power.
And if same Antminer @ 14.5 TH/s would be 4.615 times bigger it would hash at 14.5 x 4.615 = 66.92 TH/s

He should complete that calculations saying that to get to that level it would cost only $440 x 4.615 = $2030.60 in Antminers
And the cheapest Bitfury at same power draw would be $55 x 66TH/s = $3630.00
which is (2030.60 / 3630) x 100 = 56% higher in $$$