Well some mathematicians are right, but missing the point.
Using my "300hp" truck as an example. It just so happens tha HP peak is at 6500 Rpm's. In 2n gear, that equals 65 mph. Perfect for climbing the steepest interstate grade right? In theory, yes. In practice its a noisy experience. I find if I ignore the noise, I can maintain 65 up just about any highway grade. Practically speaking, I would prefer a gear like the rams 8spd has for 3rd. So ideal gearing, is perhaps not always ideal. And an 8 speed while towing is a trump card.