As Ctrl + B and Ctrl + I are used for bold and italics, it would be great if Ctrl + Shift + B and Ctrl + Shift + I could be utilized for the Strong Emphasis and Emphasis character styles, as this would make it easy to remember and learn the shortcut.
Presently these shortcuts are utilized by Subscript (.uno:SubScript all apps) and Select Text (.uno:SelectTextMode only in writer), so i was thinking that Superscript and Subscript could be switched either Ctrl + Shift + equal and Ctrl + equal (MSO) or Ctrl + period and Ctrl + comma (Google Docs), and we could find a suitable alternative for Select Text.
Somewhere I've seen (and used) # and + for sub/superscript. Maybe it's the default shortcut in German as those two buttons are located left of return. With equal I'd have problems to remember but ctrl+shift+ +/- could make sense.
Besides that I think the change is a good idea.
Alt+Shift+S - Strong Emphasis
Alt+Shift+E - Emphasis
1. Strong and Emphasis are supposed to be "semantic" rather than visual. By not using B and I (as proposed here), it does not offer a false and easy confusion between formatting (visual appearance) and character style.
2. S and E are easy mnemonics to remember.
3. Both keys are not currently used in the "default" configuration.
4. Do not require changing existing definitions.
5. (these key combinations may be achievable with one hand on some keyboards.)
6. Ctrl+Shift+E is a problematic combination in gtk. / Ctrl+Shift+S already used.
About sub- and superscripts (even though I have learned the existing definitions, it is probably a good thing to seek an easier combination)
Ctrl+Shift+, - superscript
Ctrl+, - subscript
1. are available, do not require changing other shortcuts
2. both use comma (do not have to remember which key is sub/superscript)
3. Shift should indicate superscript (mnemonic)
4. comma is probably easily accessible in most keyboard layouts.
5. Ctrl+Shift+ +/- are not offered as possible shortcut keys
6. "equal" requires a shift in some keyboard layouts
(added this topic to bug summary)
We discussed the topic in the design meeting.
While the idea is tempting, the character style Strong Emphasis is not necessarily bold and could be anything else (see also bug 136686 comment 8). Therefore the association with direct formatting is misleading.
Alt+Shift+<key> might be better but that's something for the user to customize.
Changing the super- and subscript shortcuts sounds dangerous since not every keyboard layout has the equal sign at hand (on the German layout it's shift+0). Using the comma seems to be okay but might also not be available. And there is no need to block shortcuts with functions- removing features is always way harder than adding some.