"Don't tell me I suck because I four starred Free Bird on hard"
You suck.
I completed Guitar Hero 2 on the release date within 3 hours...Then again, I'm one of those freaks you described.
And Raining Blood is easy once you can sort the HOPOs out.
In short...If you think the last tier is hard...Try beating Lou on expert (comes down to luck really), and then, complete Through The Fire and Flames.
You think you have wankers cramp?: http://zerotrace.blogspot.com/2007/11/ah-fuck-wanking-cramp.html
And of course...My Guitar Hero 3 stat page: http://www.guitarhero.com/accounts/235525
Good review though, kept me laughing