Even if you knew the "real" pricing up front, it will never work like a 'typical' market. How much do you want to bargain hunt for that next surgical procedure? How well can you even evaluate the differences between your options, what treatment really makes sense or not, etc.? And even with that, people aren't going to be entirely rational with their health care, anyway. It can often literally be a matter of life or death.
Edit: Also, the study linked to above did involve patients who knew what the prices were upfront through their insurer.