I can't help here. My cooking has gone in the dumpster since moving here. The number of times I made a Victoria Sponge, 8 halves, all in one day, to only have them all go flat and no higher than a pound coin, had me so depressed I swore I'd never bake again. (I since discovered that I was measuring in a cup the volume of the flour and not the weight in grams. Huge mistake. If you don't have a scale, get one.)
The butter, well I like it here better than in the US. The flavor, that is. But I like French butter better and I am on a mission to discover how to get some. I can't testify to its baking prowess, however. Cows are definitely fed differently here, so you may be on to something. You'll notice a huge difference in how mince/ground beef fries up.
Give Hopster a shout. She's a baking queen. In fact, I'm seeing her tomorrow; I'll mention your question.