Johnson kicks back, to his fans’ delight

Credit Jack Johnson for knowing himself and his audience. His style of laid-back folk-rock might not be to everyone's taste, but if you're attuned to it, he can serve it up to you in spades. And he did exactly that at the Comcast Center on Wednesday, dishing out nearly two hours of beachcomber vibes that did a lot to counteract the cool, cloudy evening ...