The link via Toolamba is also flatter with a lower crossing of the dividing range.
Aforementioned article is here:What would they need to do to improve the line speed to 70kph?
http://www.mmg.com.au/local-news/kyabram/freight-trains-return-to-kyabram-1.58847
Line speed will be 50 km/h which is a bit on the slow side. That works out at over 80min for 67km of track.