Based on the advice in the post linked below, I created two key commands:
Ctrl+[ = copy selection to the staff below
Ctrl+] = copy selection to the staff above
This has already saved me hours of work. In orchestration and parts writing, copying a line and then modifying it is much faster than creating it from nothing. Copy-Paste works, of course, but in a large score, every saved step is important.
Thanks for the help, Dorcio friends.
I’ve made mine Alt+Shift+N (copy to staff above) and
Alt+Shift+M (copy to staff below) because [ and ] are really not easy to make on a French layout keyboard, and it keeps consistency with N and M cross staff notes and the Alt+N and Alt+M that move selection to the staff above or below.
Not saying what you’ve done is wrong. Some fellow Doricians with different keyboard layouts could find this solution interesting. 
Mine’s Alt/Opt+Cmd…
I think I avoided Alt+( Cmd+ N) because if I don’t press Alt correctly, I create a new document… YMMV
I use Hyperkey and made it CapsLock+N/M 
I didn’t know what that was but that looks extremely useful as well. The Windows equivalent seems to be called Hyperkeys. I don’t think they’re by the same developer but they appear to do the same thing. I’m definitely going to check it out.
That looks interesting. It’s probably not so common but what happens if you’re in a text field and want to write something in all caps which happen to have the letters N or M? I always found such oddities occuring for me when I thought I was being clever with Keyboard Maestro, only to discover I couldn’t properly name a file or enter text.
Mine is the exact same (US keyboard)! I chose shift primarily because I can remember the shift key is often used for additive selection tasks, and copying is sort of like adding. Whatever helps to remember
Alt+Shift+ [N | M] is probably the most logical since it’s similar to the Dorico command to move a selection to the staff above or below. I may change to that.
I never tended to use caps lock anyway, so I just hold shift and type if I need all caps for anything. The remap to a “hyperkey” modifier is much more useful for me and works across all apps. If I ever need to create a custom shortcut for something, I can use whatever letter seems logical in that app without worrying about overriding any other shortcuts I might need.
Makes sense. I mostly use caps lock for titles and filenames, where I use all caps typically for the primary project name etc. But I don’t use it much else (and certainly not in emails or on forums!). Since it’s free I’ll give it a try!
First thing I did when I tailored Dorico was to link a fake command to Ctr+N!:)))) So I never create a new project when I fail in starting note input:))
Yes, I also use Alt Shift N / M for Duplicate to Staff Above/Below; and it was one of the first shortcuts I made, too.
I think Alt Shift M is by default something to do with Time Markers, but that’s something I use.
A toggle for Accidental Visibility, and Shift E for an Expressions Paragraph Style are the other two “must haves”, for me.