Evidence-based Medicine sounds like a good thing, until you realize that sometimes collecting the data required causes more problems than it solves. These guys took this argument to an extreme:

Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials

Conclusions As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute.

I’m sure they’ll get lots of volunteers for the study… :-)