I struck luck yesterday and had the privilege to be part of the first live rendering of Vertigo - in the car park of the BBC. I am sure Bono sung "your mind may wander" (!) rather than "you might be wondered". Other things are more difficult to decide. I guess one hears what one expects to hear. So for me it's "I can't stand..." rather than "I can sell..." and the beats have still a ring of feats.
Interestingly, the three mumbled lines were not in the order expected from the record. I am sure that on both occassions (rehearsal, then live for Top of the Pops) Bono sung "(Showman...)" or equivalent (!) first rather than last. But I am not much wiser about the conent of the lines. (I was speculating that it was something like "change it", "jars full" - an allusion to what the Gospel of John describes as Jesus' "first sign" which may fit with "showman" but this may be way off the mark - I don't know).
By the way, the band also played "All Because Of You" (great rock, slighly softer than Vertigo) and "City Of Blinding Lights" (a moving ballad for which Bono takes up the guitar) as well as "Desire". It was the first time ever that I saw the band live - it was great!