I'll take your word for it on the brewing process Ian, I am no expert on the process, alhough I am very familiar with the end product.

I remember going to England for the first time in the early 80s and discovering how different (and horrible to my taste) the Guinness was there compared to Dublin (and the locals assured me this was a comparitively good pint). I was informed that the difference was that Dublin Porter was brewed with Liffey Water, which led me to think that these people must never have seen (or smelled) the Liffey !
As a total aside I overheard someone saying on a bus the other day that they had met some US tourists in Dublin for Paddy's day who were very impressed that the river had been died Green for the Festival. (It hadn't!)

Whatever changes they have made to the process seems to have standardised the quality of pints a lot more. Its harder to get an exceptionally nice pint, but the bad ones (and they can be really disgusting) are much fewer now as well.