I'd say you've come a far way now that you're aware of the symptoms. It appears as you are playing with a low point that happens before you strike the ball.
If you complete your diagnosis you will learn a valuable lesson. So my question is: What is preventing you from having the bottom of your swing on the other side of the ball?
I went through a period of struggling with this with short pitches and that used to be the best part of my game..... Conclusions: with a thought towards the steady feel of lag pressure it goes away. The enemy is Throwaway. Plane and simple.
Aim the butt of the club (in place of pressure point #3 which sometimes drives) at your aiming point which is usually the inside aft of the ball. Hold the feel of lag pressure in the last two fingers of your left hand from the end of your backswing through impact if possible.
Hold that position to avoid any early uncocking and drive the butt end down, down, down. See the clubshaft coming down as the plane.
This is just an exercise to get you to maintain your #2 accumulator deep into the swing. You'll probably need to get a deeper pitch elbow to make this more efficient.
Once you get this, make sure you are turning and rolling the left wrist back and through.
Its a band aid, but if it works out, you will learn from it.
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Bagger
1-H "Because of questions of all kinds, reams of additional detail must be made available - but separately, and probably endlessly." Homer Kelly