Guys, let me clarify the things. That's probably an unfortunate wording that had lead to misunderstanding.
Yil is not the author of par2 library, neither the author of this feature or any other single line of code included in NZBGet.
What was meant in the phrase is that Yil has made a research of par algorithm and of source code of par library. He has published his findings on NZBGet forum and his idea (skipping the scan of undamaged files) was implemented by me in the new feature. The required patch for libpar2 was made by me as well, similar to other patches made by me years ago, which are already included in the Debian/Ubuntu fork of libpar2. The new patch is actually very small, it's just making one of the function "virtual" allowing NZBGet to intercept the call and perform verification instead of letting libpar2 doing it. Plus another small change, not related to this.
The feature is complete, it was tested by few forum members and is now available for testing for all other users in the new testing release.
Yil has many ideas. Some of them can find their way into NZBGet. We will see.
As for waiting for libpar2 upstream to review the patch - this will never happen. The libpar2 project is dead for years. I'm glad the Debian/Ubuntu team has taken the maintenance but they don't do more than integrating the submitted patches. And it's not a coincidence that the maintainer of Debian/Ubuntu fork of libpar2 is the same person who maintains NZBGet for Debian/Ubuntu.
par2cmdline vs libpar2: please don't confuse that two packages. NZBGet doesn't use par2cmdline, but only libpar2. There are not so many software which use libpar2. I know only one (in addition to NZBGet) - gpar (gnome frontend). There is no risk in integrating the new patch into your version of libpar2 because NZBGet is most likely the only program in your repository depending on it (I don't think unRAID has gpar and if it uses gnome at all, I don't know).
-- hugbug