Good point - the same reasoning would extend to the discussion of subway vs lrt.Interestingly, the main Union Station building was completed in 1920 but did not open until 1927, and reach full completion until 1930. The reason? The city couldnt decide whether or not to elevate or trench the rail corridor. They eventually decided to elevate it, which I think was a big mistake in hindsight. A trenched corridor would be much easier to bridge over and hide from the modern landscape. The station building ended up sitting empty for 7 years as they built the trainshed and the elevated approach corridors, and even when it did enter operation, a small wooden plank bridge over York street to the old union station platforms was required before the new trainshed was completed.
its rather unfortunate really, one of Toronto's grandest pieces of architecture sat unused and became the running joke of the town for the first 7 years of its life.