Recently we have entertained a new use on Physics.SE (and notably on Astronomy.SE) who has four times posted identical (or nearly so) question to both Physics and Astronomy in short order. (Not that this question is meant to pick on the user in question, just that seeing these posts has brought the situation to the forefront of my attention.)
Now, I've been known to defend the cross-site duplication of content in the past, but this feels distinctly different to me and offends sensibilities developed many years ago on the Usenet.
On the whole I feel we should discourage such intentional duplication, but I am interested to hear what other have to say.
Examples:
- Remnant of a supernova and remnant of a supernova
- Rainbow around Sun and Rainbow around Sun
- the collision of Phobos and The collision of Phobos
- two distant galaxies seen from earth and Galaxies seen from earth (despite the difference in titles the text is the same)