In many cases i would agree with you Matt. Those were just general numbers i used for a example. Reason i brought it up is that the older square faced cars tend to push more air then the modern stuff. At some point there are diminishing returns to lowering rpm. When you get to that point it requires more throttle opening to maintain speed. If it gets too bad, excessive TCC disengagement and even downshifting can result. The terrain where the majority of use is can also play a role.