While I understand your focus on achieving high speeds on straight roads, I can't help but disagree that mastery of corners is irrelevant. In fact, I'd argue that effective cornering is crucial for maintaining speed and overall performance on any cycling route.
You see, even if you're fast on the straights, neglecting your cornering skills can lead to significant speed loss and wasted energy as you struggle to regain momentum after each turn. Furthermore, poor cornering technique can increase the risk of accidents, which could result in serious injuries and setbacks in your training.
Moreover, the notion that mastering corners is a "distraction" from improving overall speed is misguided. In reality, honing your bike handling skills can directly contribute to increased speed and efficiency on the bike. By improving your ability to navigate turns smoothly and efficiently, you can maintain your momentum and conserve energy, which can then be used to increase your overall speed.
So, instead of dismissing the importance of cornering, why not embrace it as an opportunity to improve your cycling skills and overall performance? Who knows, with dedicated practice and focus on bike handling, you might just find yourself shaving off precious seconds on those turns and ultimately increasing your overall speed.