About the transborder Tango fares being $1 more than Tango+ - I remember reading somewhere here earlier in the winter (YYZ do?) that AC was trying to eliminate the Tango fare option for USA but the software for the web site didn't allow it (or something like that) so the way they eliminate it is to make the Tango $1 more than Tango plus.
It also has something to do with the code sharing with United and their fare buckets and Status miles for pretty much all of the United flights IIRC.

Congrats also to Academic...