"too much theological content"

Tim Neufeld has responded to my post where I complained a bit about people treating U2 lyrics as Christian proof-texts in a wooden, decontextualized way. I smiled at his citation from the talk 3 members of U2 gave at a retreat for musicians in their early years (I'd forgotten that "We’re a Christian band! It’s all over. We’re finished!" story) but the more interesting point is Tim's challenge: so what constitutes theological content, anyway?