David Maister has an interesting post called Client Focus and the Halo Effect, especially for us philosophy majors. In it he addresses a book by Phil Rosenzweig about faulty deductions from dubious cause-and-effect relationships. Here's the short of Maister's response:
"He [Rosenzweig] doesn’t actually question the conclusion (or belief) that customer focus causes financial performance; he challenges the validity, rigor and logic of the various studies that purport to have proven the link."
Here's my thinking. Virtually all of life's useful arguments are in fact inductive (translation: the conclusion that flows from the premises is only probable), and lack a "Cartesian certainty." The fact is you can't really deductively prove anything interesting, besides some of the following gems:

* All unmarried men are bachelors
* 2 + 2 = 4
* If it's a square it has 4 equal sides
Properly speaking, Rosenzweig is correct. But if the rooster crows enough times when the sun comes up, I can either assume the sun causes it, or I can argue that it may have some other cause. Maybe the rooster swallowed a seasonally adjusted, battery powered clock radio that goes off at sunrise, thereby creating a mild shock which causes the rooster to crow. He probably also swallowed my missing sock out of the dryer.
I haven't read Rosenzweig's book. I'm not knocking it, because his points are legitimate. I've blogged before about strange thinking in business (here, for example). However, if there are enough companies out there that can tie in a customer focus with strong financial performance, I'm going to bet heavily that whatever other factors may actually be involved, client service excellence will probably be one of them. It's hardly a leap into the unknown.