I think the answer is in the seam allowances. At this size, a small difference will have a huge impact.
I printed a Dresden plate drawn in EQ7, 16 blades (4 blades per quadrant) at 2.5 inches (to make a circle of 5 inches):
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Then, another one, 20 blades (5 blades per quadrant) at 3 inches (to make a circle of 6 inches):
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I cut one blade in each to put them side by side...
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The point of the blades are identical...
(next post - I have another picture to show...)