I'm not sure exactly if that's how most pro coaches teach it! Certainly those that have been RPT trained do! I picked up on it when doing some work with Luis Mediero and Emilio a few years back. In terms of generating power on volleys it's really important to get these combinations right as they stop you having to/trying to do too much with the arm and allow you to control the body movement for maximum effect.
Don't be upset by the results you didn't get from the work you didn't do...
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