If someone were to ask me, free of any context, if I generally like Metallica, I would say “yes.” There’s no denying that they are one of the most successful metal acts of all time, and thanks to my college freshman-year roommate I went through a spell where I was really into them. Now, however, they aren’t one of my favorite bands, but occasionally “Battery” or “Blackened,” or even “Fuel” goes down very well. Yet over the past decade, for a band that built their reputation on aggression and speed, the San Francisco thrashers have felt strangely inert.