Don Gilmore coaxes pop hooks from heavy bands. On “Crawling,” the studio ace helps LINKIN PARK achieve a riveting contrast of hazy alt-rock and boiling nu-metal rage. Bullet for My Valentine's “Your Betrayal” cultivates bruising yet melodic metalcore. Another notch in his belt is Three Days Grace's “Chalk Outline”—sizzling alt-metal boasting a huge radio-rock chorus.