Had to post this since it's the most bizarre/surprising song result I've seen in the game.
I was playing Tom Petty DLC (Renegade live version) and was playing very well. I don't think I was flawless but wasn't really playing for score so didn't notice. I then hit the solo and got my hand out of place and failed out of the song. I managed to get a perfect recovery at the end of the solo then finished out the song. The result -- gold stars!
Still can't figure out how I gold starred a song after failing out. Anyone else had a strange star result similar to that?