It's funny that you posted this - I just did my pads (with Rotex Gold) and rotors a week ago mainly due to the dust and incessant squealing. When I took off the front passenger side caliper, the outboard pad stayed on the rotor just like you described:
Disturbing is the perfect word - if this would have separated during heavy braking, I probably would be needing a lot of brake and suspension parts...maybe even front end parts altered by the car in front of me.
The good thing about this is that I don't have to listen to the brakes squealing constantly any more! And I was able to show my wife that I wasn't crazy for changing out brake pads that "didn't need to be changed"! (She thinks I'm obsessed or something - go figure

)