"A study of the effectiveness of Allied bombing yields one consistent lesson. The attacks on almost any of the target priorities; cities, ball bearings, aircraft factories, oil production, could have brought about a rapid end to the war if the initial raids had been sustained.
Harris was right."
But Harris himself was against what he called "panacea targets" such as the oil programme
how much of that was due to the fact that for most of the war hitting a precise target was impossible for most aircrew of any side I don't know but it was obviously an issue
It was only in mid/late 1944 that the air defences of Germany were degraded to any reasonable amount - until then the critical issue that you had to keep going back to targets such as railways or bridges to keep them knocked out was recipe for suicide