Certainly a double, snap-t / circle, or any prolonged anchor cast would call for a different approach than light anchor casting, but you make a good point just the same.
What is your position on the snake roll and long belly lines?
On the topic of sweeping and d-loops... I would like to compare notes with you sometime on the water. I think it's likely that everyone uses a bottom hand push (I certainly do) however the timing and extent of power is where the techniques and personal preferences come into play. We might be talking about the same approach and not know it, but then again the words do sound different and I am sure it would be worthwhile as both of us have done a considerable amount of study in casting since we last cast together at the first Flyfishing Forum speyclave at Fall City years ago.
Perhaps you could post a video of your long belly casting, as the visuals provide so much where the words seem to occlude as much as they might reveal at times.
I would gladly post some video as well; a picture is worth a thousand words.
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