If there’s anything that gunzels get excited about, it’s a parallel run — two trains running in parallel.
It must take an enormous amount of work to organise such a thing: running two heritage trains on two tracks in the same direction (only possible in specific locations), and having them overtake each other repeatedly so that everyone in each train gets a good look at every part of the other.
Of course, it happens regularly with, say, conventional suburban trains, such as this stretch between Caulfield and Moorabbin on the Frankston line.
This section has three tracks. The third track was built in the mid-1980s, and allows peak-hour express trains to overtake stopping trains.
But until quite recently, this had been woefully underused. Inspection of the 2008 timetable shows only 2 express trains overtook stoppers in the morning, and 5 in the afternoon.
The June 2010 timetables finally changed that, with current schedules showing 7 trains overtake in the morning peak, and 13 in the afternoon, thanks to more consistent (mostly) stopping patterns and express trains scheduled well into the evening shoulder-peak period.
But triplicating rail lines is now out of fashion. Because there’s very little stabling in the central city, morning trains need to be shifted back out to the suburbs after the peak, and in the afternoon trains need to be brought back in, resulting in fairly even traffic — so two tracks in one direction and only one in the other doesn’t really work.
Back in 2006 the proposal was to triplicate the Dandenong line. But following a great deal of debate and consideration, now it’s all about making better use of the existing two tracks, by standardising stopping patterns, evening out frequencies and spreading peak loads onto different trains.
And future track expansion is likely to be another pair of tracks, for instance the “Melbourne Metro” tunnel. No doubt when eventually they look at expansion further out, it will also involve an extra two tracks, not just one.
Now, if a Siemens overtaking a Comeng is a bit routine for you, and you want to see an utterly epic triple parallel run, check this video from the 1988 Aus Steam event near Melbourne, featuring Australian steam engines together with the visiting Flying Scotsman.
(By the way, any of you budding Wikipedia editors care to clean up the Aus Steam article? The grammar is terrible.)