First, Mr. Gaspe', as a Past Moderator may I say welcome to our forum.
It appears you are lining up with the camp, with Mr. Dieter being the most vocal, that holds passenger amenities should 'trump' the possibility the State of New York can save some $1.8M on the Adirondack's access to Montreal. Others such as Messrs. NSVIA, Weaver, and myself hold the possible savings to the Adirondack's sponsor should prevail.
To reiterate a point I made earlier in the discussion, Canadian National "proper' was outside the jurisdiction of the Amtrak enabling legislation (RPSA '70), which of course was not a bi-lateral treaty with Canada. As a result, and I have first hand knowledge of such, CN did a "smackdown' with regarding access; they knew Amtrak was mandated to offer International Service and they made sure Amtrak had to 'dig deep".
But how about everyone taking a deep breath and see if such a proposal is being floated to see if CN will make a "concession'; maybe they will.
Now to address one of Mr. Shivik's meaningful points, while the last time I was in Montreal, the main street to the North of Central Station was named Dorchester rather than 'Rue whatever...(and for that matter Salisbury was the Capitol of a sovereign nation named Rhodesia)", Windsor was a very Anglican looking structure yet quite functional for the volume of traffic it handled during the 70's when I last set foot in it. There should be some photos of it at the web. Suffice to say, all amenities were offered; lest we forget there was a Montreal section of The Canadian; and until they became disheartened during the '60's, CP was "up there with the best'.