Yup, it's called a "gun-down" start. That's how I learned to shoot skeet and sporting clays.
I agree, it's better to learn that way. You can learn more about proper gun fit, position, and swing/follow through. Especially important if you bird hunt. After all, who walks around bird hunting with the gun up on their shoulder anyway

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Gun-down starts used to be more commonly seen on US clay fields. It's the only legal starting position in international clays competions and up until a few years ago, same for sporting clays competion. Now, other than some old timers you rarely see anyone on a US clays field starting gun-down, except some guys practicing just before the opening of bird season.
Paul.