I neglected to mention the reason _why_ Jimmy O'Shea quit drinkin'--the moment when he realized he was "powerless over alcohol," as they say in 12-step programs.
It was like this. One Saturday afternoon, after watching a football match at the self-same pub, Jimmy O'Shea staggered out onto the street as drunk as drunk could be. Observing his meandering, zig-zag shambling down the sidewalk towards them were two nuns in full habit, walking in the opposite direction. Knowing what a hazardous, whiskey-riddled part of town they were walking through, the two Sisters were walking close to each other for safety, elbow to elbow.
As Jimmy staggered further down the street, he squinted hazily at his new obstacle, wondering how he'd get around it. The nuns were wondering much the same thing: zig-zagging as he was, Jimmy was sure to walk smack into at least one of them. At the last second, as Jimmy appeared certain to stumble into both nuns, they parted quickly, one to the left and one to the right, and walked around him.
Jimmy, befuddled, looked quickly to one side and then the other, and turned around to gaze boozily at the nuns' rapidly-departing backsides, and muttered, "how did she do that?"