ZH is really a closet busfan, so it's difficult for ZH to accept trains make faster, higher capacity PT which is unencumbered by road traffic flows. Moreover the suburbs don't end at Doncaster...
BTW it's Denis....NOT Dennis.
And we know you're a loon known for pushing trains to places where they aren't required.
Doncaster doesn't need faster, or higher capacity PT - the buses do fine.
What if such frequencies fed not just into the proposed rail link, but into other lines across the network? How high do you think the patronage would be?
Higher, but harder to calculate using simple data.