Partial
All the hints are simple l33t code.
This is about the music band Radio Head, the previous encryption method iswas vocals and the encryptor iswas Yorke(the lead signer.)
Not sure yet if code name G has some significance.
This is probably the lyrics of one of their songs. But I have yet to confirm.
Codename G might mean thethat the new encryption method is guitar and the letters A to G could be the guitar chords. and theThe numbers under might be the number of repetitionrepetitions before going to the next chord.
I suspect that e = Em(e minor)