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xkcd #2880: Sheet Bend
(imgs.xkcd.com)
Alt text:
A left-handed sheet bend creates a much weaker connection, especially under moderate loads.
It's been there for a while, just hard to spot. From doing a binary search with web.archive.org, it seems it was added on October 5th, 2016 https://web.archive.org/web/20161005090723/http://xkcd.com/