That reminds me of a paper I reviewed for my advisor when I was in grad school, in which the authors took a couple of equations that are only valid in the limit of low concentration, mashed them together so that the concentration terms canceled, and claimed that the new relationship was thus applicable at all concentrations. In defense of their claim, they had some log-log scatter plots with R^2 values in the range of 0.6-0.8, IIRC.

Even though this was the first paper I'd ever reviewed, I was not kind.