No, it wasn't in retaliation for Coventry. Nothing of the sort. The Dresden raid was just another attack on a German city, of the kind the RAF had been conducting for years.
Contrary to certain myths about the event, there was nothing special in the planning and execution of the Dresden mission. The aircraft carried the mix of high explosive and incendiary bombs typical of raids of the period, and crews followed the same standard procedures used in such attacks. Also contrary to myth is the idea that Dresden was some peaceful, idyllic city devoid of military targets. There were in fact a number of factories within the city devoted to the war effort. That it was a fresh water port and transportation hub also made it militarily significant.
Lastly, the only reason Dresden stands out was because of the freak occurrence of a firestorm, which produced casualties much higher than would have otherwise been the case. But firestorms were rare and unpredictable events which could not be generated on command. Indeed, during the entire war there were perhaps only a dozen firestorms arising from the hundreds upon hundreds of bombing raids undertaken. Had there been no firestorm in Dresden the raid itself would be little more than a footnote in the bombing campaign anals. Example: how many people are aware that the very next night after Dresden the Allies conducted a major raid against Chemnitz?
