As we all know, guitar can be a finicky instrument. Blues players sometimes will scoff upon heavier music and say, "Oh it's just downtuning and palm muting" but then struggle to do even the basics. Heavier players will sometimes look at a blues player and say, "Oh he only plays slow because he can't play fast" but then he can't let a song breathe, or play with taste. Guitar can surprise you. Recently I decided to learn John Mayer's "Stop This Train" and boy I didn't know what I was in for. Now the actual picking isn't too hard, the chord shapes are a little different than normal, but you have to chuck the strings constantly, it was a totally new skill I had to learn but I honestly feel so much better now that I can. So /r/guitar, what were you surprised by?