I also just purchased the 30-boutton Rochelle. I've been playing recorder and flute for decades and read music easlily. The Rochelle tutorial gives some instructions for how to read music, and while I did not need this information, I was impressed with how simple and useful it was.
It will help to learn to read music, but I wouldn't worry too much about "theory" at this point, if you mean learning about tonic, dominant, and subdominant chords and that kind of thing.