Hah, that attack for white became outmoded years ago. It doesn't give white enough. Nowadays, white does better with more "modern" approaches, often based on an early h3 or some other way of trying to cramp black. The very fact that white is being reduced to such cautious, defensive measures seems to indicate a long life for the M.B. When I play against people who are OTB 2100 to 2200, 200 - 300 "higher" than me, they tend to avoid it when they know I play the M.B. Even at the highest levels, solutions for black will continue to be found.
So I'm employing the benoni against much higher rated opposition with success. Is it refuted by the flick knife attack or does black live on?