At Davy Byrnes, so crucial a fixture in Dublin that Leopold Bloom ordered a gorgonzola sandwich and a glass of burgundy there in “Ulysses” – “Nice quiet bar. Nice piece of wood in that counter. Nicely planed. Like the way it curves there.” – things have changed to the degree that one city pub review congratulates it for pouring “the finest pint of Budweiser in town!”

Still, the Guinness keeps barman Stephen Delany busy much of the night.

He’s pouring to the exacting standards of regulars Roy McCutcheon and Paul Winter, who want it to take as long as it’s supposed to take, which is, officially, 119.5 seconds for the perfect pint. The first half is poured into a glass raked at 45 degrees, a process that produces a tumult of nitrogen and carbon dioxide that has to be left sitting on the bar to settle. Then, the second part of the pour, up to the brim.

“You must wait until the head rises over the top, and that’s when you start. And if you drink it when it’s first risen, the head will stay with you all the way to the bottom of the glass,” McCutcheon says.

“If you go into a pub in another country, and they just pour the Guinness straightaway …” Winter says.

” … Refuse that,” interjects McCutcheon. “You never rush the Guinness. You let it settle. Tell the barman, ‘Keep it high. No hurry.’ There’s one bar in Dublin where you can pour your own Guinness, but that is a waste of money for people who don’t know what they’re doing.”

“You’re paying in essence for a rotten Guinness. But it fools the Americans because they’re dumb,” Winter says.