Less mouse is also less RSI
AFAIK, RSI didn't exist until mice were introduced.
The way I work with new software is
1 - getting to grips with the basic functionality, if need be with the mouse but already taking note of keyboard shortcuts if indicated
2 - if I find some spare time, a quick browse of the menu tree and functionality
3 - move to using keyboard shortcuts where possible (MUCH faster than grabbing a mouse)
4 - after some use, investigate if there isn't a way to speed up things I have to do often (I was always a BIG fan of keyboard macros).
I am not a fan of a mouse - in my experience, mice may make a program easier to use but they don't half slow you down. Moving to the Mac wasn't a happy experience in that respect - I miss Home/End/PgUp/PgDn as I got used to that one-button functionality on the PC (even the extended Mac keyboard doesn't quite deliver there IMHO). Give me a keyboard any time.