Massively overestimating indeed. Sure, I'm not the most talented or obsessive member of the Rock Band community, but I have only ONE gold star song, total, at this point. I can give you 4 stars all day long though!
I also have a ridiculous number of coins from completing goals by playing in RB3. The coins were a nice idea that now have no meaning at all because HMX felt bad for the people that can't / won't start a Facebook account. I'm not saying that was the wrong decision for them to make, or that the coins were ever a seamlessly-integrated part of the challenge of the game, but they have become essentially pointless. Well, that's not quite true, they DO keep people from quitting a song in the middle a dozen or more times in an obsessive attempt to maximize a song score.
I have complete faith in Harmonix to come up with new and more organic-feeling elements to add complexity to their next rhythm game (or maybe even with tweaks / radical patches to this one, though I can't really imagine how at this point). And Blitz remains a very fun game.