At the risk of sounding like a purist, Jackass Forever is one comeback too many. I’m aware that expecting purity from this franchise is akin to drawing blood from the proverbial stone, but even when taken on its own terms, it’s safe to say that there is no Jackass without Bam Margera and Ryan Dunn – just like there wouldn’t be any Jackass sans Johnny Knoxville or Steve-O. To its credit, JF doesn’t try to replace the irreplaceable, but it does attempt to fix what’s not broken by injecting ‘new blood’ into the cast (come to think of it, it's definitely broken, and it doesn't get fixed either). ...