Rodja had a good blog on CrossFit that addressed some really good issues; I tried linking to it but it has been moved. In any case, metabolic stress =/= a good workout or even a productive workout, and often the two are confused together. A good program is highly individualised, has good monitoring + progression schemes, the S&C coaches are adequetly trained in injury + identifying weak links and allow for multi-planal exercises.
Injuries are common in the sporting world, yes. But that is not the point of the discussion.