Perhaps you don't quite understand the concept, Ed.
With solo tuning, sure the bass is tuned a tone higher, but the player plays the piece just the way he/she would normally, only it winds up sounding higher. You still read off the same solo part and do all your fingerings as normal. Of course what you play as an A actually comes out sounding as a B.
Consequently, many solo pieces conceived for solo tuning have the bass in, say D major, while the accompaniment is written in E major. The bass winds up sounding as if it is in E but the player is playing as though he/she is in D (only the bass is tuned higher).
In effect, the bass has become a transposing instrument like a trumpet or a clarinet. For a B flat clarinet, when they play a C it actually sounds as a B flat in concert pitch.
A bass in solo tuning is effectively a bass in D. When one plays a C in solo tuning, it sounds like a D.
It is a huge pain since we need to change our strings to special solo strings that are designed for the higher pitch. Lots of people are starting to transpose the piano/orchestra parts instead so they can play in standard concert tuning.
