Start with a colossal grapefruit aroma. Pile on bitterness after thumping bitterness, and ride the anarchy wherever it takes you. The caramel razor is sharp, but the resinous bite drills straight through your taste buds. For blitzing the mediocre, raising hell and revelling in the aftermath, Jack Hammer is the end of the line. The hopped-up, pucker-mouthed terminal extreme of craft brewing. This beer is bitter. Very bitter. If you push that button, don't say we didn't warn you…