The bartender holds a nice thick glass in one hand and as the door swings open, a smile widens on his face. Comedians have been laughing off their worst sets at Peter MacManus Pub on 19th St since the dawn of Improv. It’s such a relief after the crowds and the heckling and the booing to just sit in a fetid place under painted yellow fluorescent lights and take the kind of abuse you pay for.

“Charlie!” the salty old bartender calls out to the other grampa behind the stick. He hoists a bottle of cheap wine in each hand. One white, one red. “Tell Princess over there that this is our feckin’ wine list.”

The bathrooms of this Manhattan institution should be in a museum. The servers are legendary. And during the writers’ strike you could catch Alec Baldwin and half the cast of SNL joking about what they would have put on the air that week. But still, through all the cockeyed looks, the accusations of fussiness, you still see those lads back there pouring a Guinness like they’re part-timers for Walter White.

The famous Guinness two-part pour is a myth up there with the Blarney Stone. And it’s not just ye Americans who fell for it. At pubs in Cork they’re known to pre-pour the halves and then when you order yours call out, “What’s your name, lad?” and pour your initials in cursive.

What gives?

The famous Guinness two-part pour is a myth up there with the Blarney Stone. Or like saying “Guinness is Gaelic for Genius.” Two minutes from tap to table. Tip the glass at 45 degrees—or is it straight in?—pour half portion in, let settle for 90 seconds, then pour the second half in. And it’s not just ye Americans who fell for it. At pubs in Cork they’re known to pre-pour the halves and then when you order yours call out, “What’s your name, lad?” and pour your initials in cursive.

Which is lovely, I’ll admit. If time-consuming. But still a waste. Denis Leary’s Irish immigrant mother would have called it “cadology.” A term from 1930s Ireland for an elaborate hoax or joke played on a single Englishman by an entire Irish village. It comes from the Irish word “cod,” which means “bunk.”

An intrepid Buzzfeed reporter found something worse: 1:32 alleged “settle” time is roughly the length of most Guinness ads on YouTube. That’s how consistent and deep the marketing runs.

But this is MacManus, goddamnit. A fine place for a firefighter to throw up in his dress blues. The only thing one should do while waiting for a drink here is be having another drink. When the next comedy crew gets out of their unpaid show, Charlie picks up the pace. He pours about two-thirds of a Guinness, finishes the rest of the drink order and then stuffs the last creamy third on top. The result is something akin to a root beer float. In a minute it settles into the lovely, iconic blonde we all know.

Is Charlie rushing the set with that pour? Perhaps he, like the comedians in front of him, saw the red light flash and tried to get all his material in.

The real irony is that it was incredulous beer drinkers themselves who gave birth to the two-part pour in the 1950s. When Guinness switched from wood kegs to metal, the devout thought of it like the Pope becoming a Methodist. The two-part pour, necessary during the transition, was no longer needed with the dawn of new dispenser technology. But Guinness stuck with the whole “good things come to those who wait” concept to hold onto the faithful—and it has endured to this day.

Now, surely you’ve noticed that Guinness runs from a separate tap than the Molsons and Narragansetts of the world. If not you’ll notice it next time you wait five minutes for a Stout. Check the taps at any pub. Twelve in a row and then that lovely black stick.

While most beers are carbonated just on CO2, Guinness comes exclusively in kegs pressurized by 75 percent nitrogen and 25 percent carbon dioxide. A nitro tap pours out something a little creamier that interacts a bit more with the environment when the nitrogen dissipates. Hence putting Walter White behind the bar.

In the era before the microbrew, Guinness of course stood alone. The lightest dark beer (only 125 calories per 12 ounces versus 110 in Bud Light), the most complex in color. But in the era of the single-keg, do we still need it?

Yes. Yes we do. And in the age of Instagram there is nothing wrong with getting that perfect, iconic pour straight from the bartender you’re overtipping to hand you a beer. It is worth noting, however, that you’ll get the same result in the time it takes for the waitress to get through the St. Paddy’s Day crowd to your table.

A Guinness needs a moment to settle. If you rush it will taste flat. That’s the nitrogen mixture which takes a minute to formulate. But is that time spent behind the bar in a half-full glass? On the server’s tray? Or at your table while the Nitrogen dissipates along with your patience? You could argue the merits of each and by the time it’s your turn to state your case, the beer is ready to drink.

Perhaps you have a pink-skinned friend who looks forward to this day all year round and he wants to have a clink-and-drink right at the 5 O’clock whistle. If you’re a thinking lad and you know about as much about Chemistry as Charlie, pour it on an angle like any other beer, let the foam settle and take a sip when it looks dark on the bottom.

And try not to think about how we still don’t have a united Ireland, nor how Saint Patrick was a German kidnapped by the Irish Warlord Niall of the Nine Hostages and forced into slavery. Nay, just daydream about a 24-year-old Jennifer Aniston rocking LA Gears and starring in the original Leprechaun, raise that glass and say, Slaínte!

Because here’s the the thing: I spent my twenties behind a bar. And I did the presto-chango cadology because I worked for tips—and explaining to each drunk why pouring fast saves time is a waste of time. But now when I’m in my old bar after hours and the stools are up and I step back there to pour a stout for myself alone… I still go through the rigamarole. It just feels beastly not to.