I’ve been told this was done mainly to steer the boat away from the side of the tunnels while the people in the rear used a pole to actually propel it. I’d love to know if this is true or not, there’s precious few resources about the subject.

Yeah, gonna need a source on this one. The streets are clear, there’s no fires, seems less like “one night” and more “after an entire campaign of terror bombing”. But if you really want to see what the strategic bombing campaigns were capable of, look up the aftermath of cologne. The re were only a handful of buildings that surived, I think in the double digits though I’ve seen people say it was everything except the cathedral (we didn’t bomb that because we were using it to orient the bombing runs).