Mechanics as in how technology works. Disney stated that everything is not in the same [i]level[/i] of canon as the movies, but SW works in different levels of canon, IE if something like a Star Destroyers needs an explanation on how it was built, runs, works, and power credentials, then books/games ARE canon until the main voice behind SW (that being Disney) comes up with their own answer and makes the previous works invalid. As far as Disney's statements go, they haven't said anything about the canon pyramid other than that books, games, and other media are not on the same tier as the movies which was already common knowledge even before Disney bought SW.