Get constant motion if you want tricky. Jesus Christ!
Solo. I have yet to pass it using a full bar of energy. It's insane, ridiculously fast and annoying as well.
I keep my fingers on R-O rather than G-B and just reach to use the green when needed. The best advice is obviously just practice, the more you do, the more natural things will become and the better you will get.
OI! YOU! get back on rock band and send me a damn invite Si!