Haha, no, I've just been thinking about our discussion on this subject recently and I've decided you're wrong.
I have to disagree that first hand experience is misleading, because that's what happened - it is the experience. If anything, watching something back is misleading, for better or worse. When a band play live they're doing it for the audience that's there, which is kind of all that matters. It's like when people complain about the setlists getting stale because they watch crappy footage of every single show on YouTube and look up what they played on Setlist.fm - totally irrelevant. If it sounds good to those in attendance, that's the important thing.
I think it should be taken into account that playing live you get one chance to get it right. When you're doing 30 songs over the course of two hours, plus interacting with the audience and running around the whole time, you're not gonna sound as good as you do in the studio, when you can spend as long as you want getting the best possible take, and probably only do a song or two a day. Live stuff never has the primary function of being watched back, it's meant to be a good experience for those there at the time. So unless you're saying you thought he sucked at Brixton, your argument is invalid.
I guess what I'm really trying to say is that I don't even necessarily disagree with you, you're just being overly critical and should give him a break