I did get a chance to try a Guiness a little closer to the source when I was in London, and it was much better than the shit that makes it over seas.
It’s actually much more likely that the pub doesn’t have a clue how to deal with Guinness. It happens a lot in British pubs too that are chain or don’t sell a lot of it. The pipes need to be run clean at the end of every day, which isn’t always the case with lagers and ales and it’s at its best when it’s being ordered regularly and there’s a good consistency flow through the pipes. I’d say some more Irish areas over there might be ok?
Come to Ireland though sometime and we’ll get you a good pint.