He never stated it's faster. And it likely isn't if the pattern is big enough: GPU's can't access memory nearly as well as CPUs.
GPUs suck at accessing main memory.But they're very, very good at accessing on-board memory. See, for example (from a couple of years ago)
http://blog.cudachess.org/2009/07/cpu-vs-cuda-gpu-memory-bandwidth/
Quote
CUDA-enabled GPU offers up to 8X the speed of main memory and 4X the speed of L1-cache compared to a moderne CPU...
I predict it'll take... mmm... 3 weeks after source code is released for the first faster-on-a-GPU solidcoin 2.0 closed-source miner to come out. 8 weeks until there's an open-source one available.But my predictions are often wrong.