About a year ago, I took the "Knitting for SPEED and EFFICIENCY" class taught by the Yarn Harlot at A Verb For Keeping Warm. Great class and interesting technique.
I practice on some garter and then started on this one by one ribbed scarf. It's true that purling goes pretty quickly with this method. It took me a couple nights of practice to get the tensioning right. Having trouble keeping the working needle tucked under my arm--it slides around. Also, having trouble keeping my right hand braced against the working needle.