I think your talking about Charlie Ritz not Lefty Krey. In his book "A fly fishers life" Ritz advocates the use of a compact casting stroke and bending the wrist to help develop line speed, however, Ritz he bent his wrist in the vertical plane, not the horizontal plane as shown in JC's diagrams. The Ritz method is a lot different than the Lefty Krey move your elbow back & forth style of casting. Cheers.