Just a quick reminder that using gaussian blurs (as the script does) works great so long as the angles aren't too acute. You can see from this example (with the difference from the original after each option) how the shape on the right doesn't get correctly radiused with the script.
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The shrink/grow/shrink (or grow/shrink/grow) technique has its own issues, namely if the shrink or grow processes cause the selection to self intersect, it gets messed up.
-Rob A.