superelevation
Active Member
I don't understand interlining in situations other than a bunch of branch lines with lots of extra headway in their timetables merging together to utilize a central corridor more effectively. Interlining to go to York U would suggest that Line 4 and Line 1 south of Sheppard West is the part of line with a lot of extra headway... but downtown is the busiest part of Line 1, not York U, so extending the frequent Line 1 service to York U is the most efficient way to add capacity to York U. Interlining to go to York U does not add a net benefit because it somehow suggests that someone getting on a subway downtown to go to York U waiting for a few trains to pass before boarding is more convenient than someone on Line 4 walking downstairs at Downsview to transfer to a frequent service line... but waiting longer in a crowded station is not more convenient. When low ridership branches come together into a central corridor there is nobody waiting longer... the frequency of the branches was tuned to their ridership and the central corridor gets more service than it would have so everybody wins. However, this branching only works to the point that each branch is getting the service level they need. At the point the merging of branches is limiting a branch so another branch can fit into the central corridor schedule, it is better to have transfers so each line can meet their capacity needs independently.
The difference is there is a big difference in demand from Yonge to Spadina and so running the same headway doesn’t make sense, theres even less demand on most of the TYSSE than on most of Spadina.
This would utilize that surplus capacity (which will be there for decades at this rate) to improve connectivity and reduce transfers, it makes sense.
Remember Line 1 is really 2 distinct lines