If anyone's interested in reading more about this, I'd highly recommend the book Birth of the Shinkansen by Tetsuo Shimomae. It's 300 pages goes in-depth into how various technological barriers were solved and how they maintained and improved the technology over the past 6 decades, and also gives you a bit of an insight over the cultural norms that also contributed to that record. Even if you're not into trains, it's a very cool read if you're interested in technology/engineering/Japanese culture.