steamtostay wrote:
From a technical point of view re: eliminating level crossings, it is actually more beneficial to the rail network if each station is elevated relative to the rest of the line; this way the incline aids deceleration on arrival and acceleration on departure from the stations.
This effect can also be gained underground, but only if entire sections of track are placed underground at once, rather than one station at a time or similar. However if that does happen, it allows for a rationalisation and.or repositioning of all stations on the given route, as well as a straightening of said route to reduce the intermediate setion lengths.
Of course all this will only make a signifigant difference over a considerably lengthly route; at least 6 or 7 stations before any true value can be accomplished.
Popular to common belief, this is not how the City Loop was designed. Flagstaff is the only one where this occurs, with a minor amount at Parliament. Melbourne Central is the complete opposite.