Originally Posted by stevendorechester

I searched LGA-YUL and that was the cheapest option. It ended up being two separate tickets on AA. As for illegal routings airlines know better than two allow. I' m pretty sure it's changed now for OTA's. What was wrong about this is some unsuspecting passengers would book these fares and could be in trouble in case of IROPs or if an agent decides to not allow them to check in, especially in the case of an OTA putting it on the same PNR.

I still see this on ITA matrix where they show a fare via Canada on a US domestic journey, though usually quite expensive but not always; I remember recently seeing SEA-YVR-HNL on WS offered cheaper than with US cariers.