I play as a Defensive Dman and my slap shot is much more powerful then my wrister, so it would be a useful piece of information.
My only real idea on it would be to time the stick movements correctly with or without vision control (LT). Due to being so far away from the net, I don't think vision control (LT) really matters. It's easy enough to execute a wrister one timer with or with out vision control (LT), but am at a bit of a loss for a slap shot one timer. Most of my attempts in game have not turn out well.

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