people need to stop being so nervous about this. eno and lanois are very talented musicians and producers, and knowing that I can say, if Lanois and Eno recycled something else they did once, they did so either because a.) it was a good recontextualization of the music, or b.) because it was the best possible sample to use.
Either one of those is fine. But who cares, it's gorgeous. I'm thankful U2 gave Eno and Lanois writing credits, because the album has an element of freshness that's been missing.