When another file opened from the desktop it opens in a new window, also with the sidebar open..
"Why not just hit paste twice?"
Didn't understand what you would achieve with this..
Anyway, there is no utility on pasting something on top of the same thing, so of course no one does it. Therefore, no consistency would be broken, but functionality would be added.
The best interfaces are the ones which add functionality in a subliminal way, not necessarily in a explicit form. Why memorize an extra shortcut, or take extra space on the keyboard, when it could be achieved with the combination of 2 familiar ones?
If you prefer the duplicate command, you can keep using it :)
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