The Russians call it "imitatsiya" - shadow swinging in order to properly reinforce a neuro-musuclar pathway. They use it a lot!
I love shadow swings and frequently ask my players to shadow (especially with their eyes closed, so they have to concentrate on the feel of the swing). I tend to use it most when correcting issues with swings, the moment the skill breaks down, they shadow the correct swing to reinforce the circuit.
Don't be upset by the results you didn't get from the work you didn't do...
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