Riding a bike down a rough mountain hillside can be pretty sketchy. Even modern full-squish bikes with disc brakes still don't remove all the various trail features that threaten your general well-being and intactness. Knobby tires were a game changer over the balloon tires the boys back in Marin, CA were rocking on their clunkers. We reckon there's still a big contingent of people out there who like to throw down and get rowdy.
One way of doing that is mixing in a little new school with the old school. The Rock Razor blends the advantages of stout side cornering knobs with a shaved-down minimal center tread. This design puts a premium on fast, allowing riders to carry heaps of speed when bombing fall line down the hill, flick their way through tight corners, and carve around berms like a banking fighter jet. You'd better bring your A-game with this tire because if things go wrong, it's probably too late to do anything about it. Braking is not this tire's strong suit. But if your victory speeches contain lines like "Go for broke" (speaking of which, this tire isn't cheap) and "Let it all hang out," then this tire might warrant some consideration.