I asked one question over on skeptics.stackexchange.com about empirical evidence for programmer productivity. One user then prompted me that I'd have more luck over on programmers.stackexchange.com, so I cross posted there as it clearly fits both sites.
I thought until very recently that it's not encouraged to cross post until Robert Cartaino stated:
There is no concept of closing as a duplicate on another site. Each site is autonomous. This is a rare case of where the question might actually be appropriate on BOTH sites-- one set of answer from the point of view of an expert on the subject, the other from a skeptic challenging the science.
Which seem to say that each site is autonomous and there are cases where one question might be appropriate on both sites such as the question on skeptics.SE Is stretching beneficial after exercise? and the question over on fitness.SE Should I stretch after exercise?.
So I referenced the above reason for cross posting when I was challenged by moderator ChrisF on programmers.SE. Then later moterator Sklivvz over on skeptics.SE challenged me linking to an older statement by Jeff Atwood that says this is probably not okay and that you should ask, delete and re-ask questions, citing that it's a slippery slope to allow such a thing:
Allowing cross-posting is a slippery slope.
If you might have slightly better odds of getting an answer by posting it on two sites, well, by gum, why not maximize your odds by posting it on twenty sites!
There are some questions which fall into grey areas between sites, and I think it's OK to ask and delete, then re-ask if you feel you have asked on the wrong site.
But as a general rule, do not cross-post questions, please. Pick a site and go with it.
I'd like to point out that I did pick one site first and only cross-posted when prompted. Is it acceptable in this case to cross point, and what is the rule in general? Perhaps the greater Stack Exchange community could benefit from examples of when it's appropriate (if ever) and when it's not. Most relevant to my case Jeff Atwood recently said:
It is considered outright abuse to copy and paste questions across the network.
If you tailor your question to adapt it to the different audiences on a site -- and genuinely make an effort to to so -- then it can be allowed. But copying and pasting is indefensible.
And Robert Cartino said:
There are somewhat rare cases where you may benefit by asking different groups of users a similar question, because the context of their expertise will provide a different perspective.
But if you are asking the same question of two different groups simply to reach a larger audience, I would frown upon that. Ask the question first on the site you feel will most likely provide the best answer. If you do not receive an adequate answer, then it might be okay to ask your question again to another group of users — as long as the question is on topic and appropriate for that second site.
But cutting-and-pasting between two sites is never okay. If you want a different perspective, you should phrase the question specifically for that group.