Found in 2 comments on Hacker News
That consistency is phenomenally important for the user.

I had a quick skim, Elementary talk good sense. It's this apparent trivia that makes the experience. Like can dialogue text be copied, or how a menu opens, and why. Or what shortcut keys to use and when. Or always use the default file open as it'll automatically upgrade visuals and at least some capability when the next OS release comes along. :)

Play along and the user will know how to print, open, copy, preview and a hundred other things on the first ever use of your new program leaving them just to learn the unique new thing.

I kept my Amiga Guidelines phonebook[1] for years after the machine was effectively dead as the principles and explanations were still sound. The Apple Guidelines[2] were worth owning whether you used a Mac or not, again for the principles, and would often get recommended. I had a copy years before I ever touched a Mac! Life got simpler when they were all online.

I don't think it matters where you take cues from, so long as you are internally consistent, and apps carry on that consistency.

[1] http://www.amazon.com/AMIGA-User-Interface-Style-Guide/dp/02... [2] http://www.amazon.com/Macintosh-Human-Interface-Guidelines-C...

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