Had an interesting experience with IDB last week when my MUC-YVR flight was delayed, leading to a 43 min connection time for my onward YVR-YEG flight. With no bags and NEXUS I arrived at the gate for my onward flight as zone 3 started boarding, but was denied my seat in 2A. Due to the MUC-YVR delay, I was told that "the system" automatically offloaded me and rebooked me on the next flight (not a huge deal - the next flight was about an hour later).

This struck me as IDB, so I wrote in with a request for compensation, almost more out of curiosity than anything. I was told that "in situations of minimum connecting times not being met, Denied Boarding Compensation does not apply." International-domestic MCT at YVR is a very generous 100 minutes, so obviously the MUC-YVR delay caused me to drop below MCT. But I swear I've had delays leading to missed MCT where I wasn't offloaded - it must only happen when the onward flight is overbooked (?). And when I used to fly UA a lot I remember being protected on later flights but not offloaded.

I also know there was a related Nova Scotia court case several years ago where it seemed clear that MCT-related auto-rebookings are trumped by the Tariff rules regarding on-time check-in and timely availability to board.

I'm not going to push it anymore (I did get a $200 voucher, which seems pretty fair for a 1 hour delay), but I'm curious about similar experiences.