"But honest question because I really don't know: does that leg lift as the first move exist in any other MYJ form? Is it possible the movement could have been added in then? (Van)
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***I assume you mean any other wing chun system/lineage. Not really sure, but I think that HFY might have it in a form as well - because I know that they use the move. Perhaps duende or JPofAZ might want to answer that.