Indeed he did, and with good reason... It's very hard to control an open string as it rings. Many times when you mute an open string you'll get an unintended harmonic. I personally prefer to play very few open notes. Most of the time I stay above the 5th fret, though on occasion I'm down on a low G. Open strings for me really only work for me in the extremely rare instance that I'm playing a whole note or longer and when that instance arises, 99 times out of 100 I'm dropping a bomb that needs to be low and powerful, a situation that calls for an open E or B (or similar ridiculously low frequency note.) Those need absolutely no real control...