Comment by bombcar

The USA has the freight problem because trains can't pass each other unless there is a siding long enough for the train that is being passed; and the freight trains are too long.

Where there's double-track (or more) it's not as big an issue because the train can pass on the other side of the track (tracks are often handled as if they were a road with one lane going in one direction and the other going the other way, but you can swap around with signaling).

The other major solution (bandaid) is to add dwell time at stations so that there's room to make up - the timetable says when the train will leave not when it will arrive, and if it normally arrives five minutes early, it just waits; if it lost time and arrives one minute before departure, it will just be there a minute and the lost time is made up.

But while that may reduce the "worst case" scenario, it does make the average travel time longer.