Hmm, wish Infil and I knew about "one" being so easy, and we'd have gotten the 1 million on that instead of trying TTFAF (900K was nice though)!!
Your GH skills wont help you an ounce more than finger dexterity on a real guitar, which your right hand, knowledge, string passing ability, strength, pattern recognition, hand movements, etc., wouldn't be able to do for quite some time. To use 5 frets next to eachother like in guitar hero is unheard on a guitar - that is 5 straight notes in the chromatic scale! Rather, guitar ALWAYS skips frets, there is no such thing as a "1234" simple pattern, and instead of moving 1 fret without looking, its moving across 12, granted you can look.
You'd be a bit more dexterous though and would probably enjoy it, the thing is you don't really get to solo or play any riffs that are fast at all for quite a few months, and even playing the easiest of songs from GH would be out of the realm!