I am not counting that useless doc check that Amtrak does at NYP, which I agree is stupid and redundant, and neither CBSA nor CBP pay one bit of attention to those stupid baggage tags. In terms of process, though, the experience of inspections about is the same whether it takes place at US Preclearance or not.
You also have to take all bags off the buses, too, both directions, at least at Pacific Highway and Niagara Falls.
Neither CBP nor CBSA are going to go back to onboard inspections. Both agencies really hate it. It is one of the things preventing resumption of Montrealer type service, neither agency will support another train that has to have onboard inspection, so getting that service back will require a Port of Entry facility at Gare Central. I am actually a bit surprised the agencies allowed the Adirondack to resume with onboard inspections, but I guess it was "grandfathered" in.
Both CBSA and CBP are going to use the "bus" model of inspection at the border for rail service for any future service where they can't do a terminal entry inspection/preclearance. That would probably include Detroit/Windsor or Port Huron/Sarnia if they ever get Chicago-Toronto service back up. That will use the Maple Leaf model, not the Cascades model, because it would not run sealed for the long run within Canada. The best that can be hoped for is that CBSA moves into the Niagara Falls, NY station for inspections, which has high platforms, was designed with dual use in mind, and Canada now how has Preclearance rights for rail in the US. Hopefully any other future service that can't run sealed and does terminal inspection uses a single facility on one side of the border or other.
