I had a fit done a few years ago to solve a hip problem (created by running - which I gave up on - but still bothered me on strong efforts on the bike). Had it done at Boulder Center for Sports Medicine. Cured the problem. The Center is run by, and the the folks there are trained by, Andy Pruitt - who more or less invented the modern "science" of bike fitting. They will also work with your insurance company to pay the costs - check with them first though.
Interestingly, one of the online bike racing sites (either Velonews or Cylingnews) recently covered a symposium that included a session on bike fit. Pruitt was there along with a couple other professionals and on a few questions they disagreed as to how fit can help a specific problem.
So, as stated above, there are various schools of thought. BCSM worked for me.
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