I think that's a great analogy. If you follow the watertight instructions of AVRT you will achieve what seems impossible and fix your addictiion in a permanent and secure way.
Just as the rain will come again (and again if you're in England!) so will AV. But in AVRT, the AV is not the addiction, it's the source of the addiction. The addiction is the ambivalence of mind brought about by the AV. Could I just have one? Will I really never drink again? And the AVRT techniques of recognition and separation will end this ambivalence and wash the offending AV away as if it's no more tenacious than raindrops on a windcreen.