[QUOTE=MikeG]
I would not be surprised to find that the correllation is “not type of pour=quality” but rather “type of pour=owner cares about lines, N/CO2 mix, and other external factors” that makes the difference. It’s an extremely reliable bellwether in my experience.
[/QUOTE]
I would definitely tend towards this explanation. I too, would agree, that with places that do one-shot pours tend to pour bad Guinnesses. I also think these sorts of places probably serve a lot less Guinness, and therefore it isn’t as fresh, because surely the Guinness aficionados will flock to places that follow the ritual. Just pure speculation on my part. Like I said, within a single bar, having a Guinness pulled all-at-once or in two parts, I haven’t discerned any difference in taste.