Every train doesn't have to stop at all 27 stops. You can run a super-express that stops at 5 stops every 30 minutes, an express that stops at 10 stops every ho

Every train doesn't have to stop at all 27 stops. You can run a super-express that stops at 5 stops every 30 minutes, an express that stops at 10 stops every hour and a regular service that stops at every station every 2 hours. The schedule is constructed in such a way that the faster train passes the slower one while it's stopped at a station. Shinkansen between Tokyo and Osaka is the busiest rail line in the world and there are a lot of stations between these two cities. The fastest train, Nozomi only has 6 stops and runs every 15 minutes.