Guitar Hero 7 was well under way, experimented with six-stringed controller before cancellation
It seems that Activision had done a fair bit of experimenting with the Guitar Hero franchise before they abandoned it completely back at the beginning of 2011.
According to new reports Guitar Hero 7 was well under way and Activision had ditched the microphone and drum kit and experiment with a new six-string guitar controller before eventually deciding to cancel the whole project.
The six-string controller which replaced the strum bar with six strings was eventually abandoned because it was not responsive enough but development continued after that until Eric Hirschberg, president and CEO of Activision Publishing visited the developer Vicarious Visions about half way through GH7's two year development cycle and decided that the project was not worth pursuing.
The source of the reports (anonymous, of course) also suggested, "GH7's woes as emblematic of [developer Vicarious Visions] tendency to overreach with its console games".
Given how well Sleeping Dogs (which began its life as True Crime: Hong Kong and was cancelled at the same time as Guitar Hero) turned out it would be fair to wonder what might have been had Activision given GH7 the time and the support needed to complete the project.