I had a very stringy brisket in a roadside bistro 20 years ago, somewhere near Lens (France). And wine flowed pretty freely too.

It was not beef that is for sure. It was perfectly edible, and tender - probably boiled..

My mother used to refer to the war years in the UK, when a lump of beef would get a lot tougher in places - she reckoned they (Argentinians?) folded the beef with a slice of horse.