Simple Region intersection failed

Grasshopper
1

Here is a simple example of two closed planar curves in which "region intersection " failed to compute…
Any idea or explanation ??error 7.gh (4.9 KB)

2

I’m bumping this topic because I also find Region intersection to be quite feeble.

3

Yet if you feed it with Boundary Surfaces, in this instance, it works. Curious.

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