Best drills to correct In - to - Out swing path?

[TomATL]

In my experience, I think Burner is exactly right. Inside-out has always been a real problem for me, and what has helped is not a drill, but a swing thought. If I consciously try to to be LEFT OF THE BALL (I'm right handed) AND CLOSED after impact, the improvement is immediate and dramatic.

Hope that, or something you pick up here, helps!