Guinness has pulled a fast one plenty of times in the past. I recall a wee scandal back in the 1980s, when it was revealed that, each summer, they reduced the strength of their stout (watered it down) while nobody was likely to notice; by the winter, everyone was used to the weaker version, so they could water it still further the following summer. They had to stop doing that when the law was changed to oblige brewers to tell their customers what the strength of their beer was. They have also made massive donations to the Conservative party in the UK over the years (as do most brewers, regrettably) in order to ensure special treatment. The Guinness/Tennant family has also been directly responsible for some pretty disgraceful things, perhaps most notably the deliberate marginalisation of the native population of Mustique, but that's another story. I like the beer, but I despise the company that makes it, and the people who own that company. What can you do, eh?