D71: Dagnammit

I thought that figuring out this seam allowance caper would align the rest of the bag, like it did for the 1:3 bag.  But it hasn't! IT HAS NOT!

Left: arranged so that the points are aligned.  Right: flat, with no adjusting, points not aligned.

Below is a better pic of the bag with the body of the bag shifted so that the points line up.  It would require the seam on one side to be 1cm deeper at the bag base.  You can see how that would clip off a portion of the left corner, shortening and narrowing that side and making it asymmetrical in the body, just so the tips aren't!

The white line is the seam I would sew to make the points align. It ends 1cm from the original.

I imagine, if I wanted, I could arrange it so that both points have a half cm taken off and it would align the points.  However, at this stage, the only other things I could imagine working are either

1. try folding from the end, rather than using the maths (this effort) or by tilting the ends away from the centre (first effort), or;
2. reverse engineering the whole thing. 

I now officially feel that my attention-to-benefit ratio is way off and that, short of breaking a leg and being desperate for occupancy, I shan't be giving this problem any more attention. SNIPPITY SNIP COMRADES!
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