I remember reading some time ago that there is a real difficulty running passenger trains and freight trains over the same rails. With freight, you can tolerate bumps at the rail-join points, and freight tends to create such bumps because the heavy loads push the rails slightly out of place. Also, freight routes should be limited to a 2% grade, whereas 4% can be tolerated for the lighter passenger cars. Have these problems been mitigated on the Koralm Railway? Anyone know how?