We already have enough things to worry about causing delays without bringing an international border into the picture.
Working backwards.........pre-clearance customs can largely erase the issue of delays associated w/the border.
An option mentioned in that piece.
That said, while I would like to see more frequent train connections btw Buffalo and Toronto, and I do think there's a market for that, I don't see the GO Train as the right solution.
Whether one uses VIA or Amtrak or a private operator, I think you need both faster and more comfortable rolling stock to make that trip work well.
I also think pre-clearance customs are a must.
A whole slew of things need to happen before the idea is ready for serious conversation.
On our side of the border, we need to see the complete package of improvements to the NF-Hamilton trackage that have already been envisioned in the GO expansion plans.
Likewise, improvements in the LSW corridor are needed merely to shift to 15M GO Service, let alone add additional train movements. Those need to occur.
To generate higher speeds, further investments will be needed (I'm not talking HSR, but rather maximizing current maximum speeds, and perhaps contemplating an upward shift in the max to 200km/ph)
Beyond that, on the US side, Buffalo needs to build its new Amtrak station, and that facility would likely require alteration as I don't believe it contemplated customs services.
Once all of that is done, I expect that there may be market for service 4x each way each day btw Buffalo and Toronto, maybe more during the peak seasons.
But we're a long way off.
Let's review the idea in 2024!